Welcome to the VR Party! We have 2 REAL choices and a dozen or so garbage options in the third party world. I'm going to focus on PC VR, I really dont give a shit personally about PSVR, and after small time Ive spent with it and 1 buddy who has it, I'm just not interested. IF you have some cool stuff about it, Let me know. I'll add it

The Contenders (Current)
Oculus Rift

The Oculus Rift costs $399 USD. It comes with the headset, two tracking cameras, a remote, and two touch controllers. For people who previously bought a standalone rift, Touch can be purchased for $99 USD. It comes with the two controllers and another camera. Another camera can be purchased for $59 USD, and you can have up to four cameras. In ear headphones can be purchased for $49 USD, and they have the proprietary connector the current Rift headphones use. The Rift no longer comes with an xbox controller or wireless dongle, though some stores still might have old stock that does come with it.
The Touch controllers each have a trigger, a grip button, two face buttons, a joystick and an Oculus Home button.
HTC Vive

The HTC Vive costs $599 USD. It comes with the headset, two motion controllers, two base stations, and a lot of cables. It also comes with a breakout box. The breakout box sends power to the headset and will also convert minidisplayport to HDMI. With its motion controllers, Accesories are available on the HTC Vive website. This includes replacement controllers ($129.99 USD each), base stations ($134.99 each), a deluxe audio strap ($99.99), facial interfaces and cables.
Each motion controller has a trigger, two grip buttons on the side (though both act as the same button), a menu button, a system button for opening the SteamVR overlay, and a trackpad that can be just a trackpad or four separate buttons.
The Vive also has a forward facing camera. It can be set up so you can press the system button twice and a tron-like image appears on screen which shows a camera feed of what is in front of you. You can also set it up so it shows up as a normal color image attached to your controller while in the steam overlay. This is helpful for finding where you need to put your controllers down to take off the headset or if someone is in the room and you need to see them.
In the end it doesn't really matter, they both play the same games(Mostly). Buy whichever you think is best (Rift/Vive).
Motion controllers
Motion controllers are by far the best way to interact with a game in VR (unless it is the type of game that lends itself to a different piece of niche hardware like a joystick or steering wheel). This is how you get true immersion because you can interact with the virtual world by picking things up and hitting buttons and switches in the world.
Both now have some sort of controls included. Generally its agreed that the Rift Touch controllers are better than the Vive wands for a handful of reasons. Hot swapable batteries, feel more like working hands in a game/world, and the joysticks dont get stuck like the trackpads do on the vive (less repair crap). Again lots of personal opinion here but I think most people who own both agree that the touch is the way to go.
Room Scale
This is the most immersive of the three choices. You define your tracking area based on how much room you have in your physical space. Now you can walk around this area in VR to interact with your game. This is great for games that don't require you to move around a lot. You're going to want at least a 2 meter square area for this.
Hardware
The Rift and Vive both take a different stance on audio. The Rift provides you with removable headphones. They are decent enough quality for use but they are on ear and not over ear. This means that sounds from outside the headset will creep in. They are also a proprietary connector and there is no onboard audio jack. If you want to roll your own audio on the Rift, you will need to either use wireless headphones or run a cable all the way back to your computer which means another cable.
The Vive comes with some questionable quality earbuds and a cable that comes out the back of the Vive that you can plug whatever headphones you want into. Keep in mind that this jack is on the headset, so if you have a long headphone cable, you have to find your own way to deal with that. Either get a shorter cable or use wireless headphones.
Software
When you launch a game in Oculus Home, it automatically sends the audio to the Rift headphones. If you want to use your own headphones that don't use the proprietary connector, you'll have to mess with some settings to get the audio to your headphones.
By default, SteamVR doesn't reroute any audio, it just comes out your normal speakers. If you use wireless headphones, no problem, you're good to go. The SteamVR settings allow you to have it change your audio settings when it starts up and shuts down. When SteamVR starts, you can have it set the default audio device to your headset. This does not mean "whatever headset," this means whichever headset you choose to be the audio device. If you have more than one headset and you have SteamVR change to the vive audio and then you try to use your Rift, it will still try to send audio to the Vive until you change the setting. This isn't ideal.
Microphones
Both the Rift and Vive have a microphone built in. I personally haven't used the Rift microphone but I have tried the Vive microphone. While it was decent enough quality, it's location meant it kept picking up my breathing as if I was blowing into microphone. This is something a lot of people suffer with so depending on how big your dome is, you may have this breathing problem too. I've personally since moved to a wireless headset since breathing on stream is really annoying to viewers, and its SUPER annoying in games you have to mute people, assuming you even can. Some games don't have the option

Games
This section could be giant but I'll try to leave some things for new posts.
Robo Recall (Rift Exclusive, Free for Oculus Touch owners)
Fantastic teleport movement shooter. Gunplay is awesome, and its super well polished. Its one of the first games I booted up and still remains a fav. Also runs super well on shitty hardware.
Onward
Mil Sim Counter Strike sort of game. Highly recommend it if you want something that feels "real" when it comes to shooting mechanics, gun feel, and bullet damage. Headshots are dead, Period. None of that 2 to the head bullshit.
Arizona Sunshine
Personally, I picked this up at full price and some might argue its not worth that much since theres a lot of newer games that are better. I agree, and disagree. I really enjoyed the play through of this, and its still fun to jump into horde modes online. Only problem is, MP is a bit on the dead side since its older. So if you're cool paying movie theater money for a game thats 4-6 hours? Cool. Its worth it.
Soundboxing
Soundboxing is a VR music video kickboxing game where you create the beats! Yes that line stolen from the steam store. Its the best description of it. Its a ton of fun and really a good workout. IF you enjoy beat games, and working up a sweat, pick it up.
Catlateral Damage
Gimmick game, Laughed my ass off, Great for demos with people. Just, don't buy it full price.
Bullets and More VR
1 Dev Patrick.
Dozen game modes.
Current leader in Battle Royale mode for VR (Stand out might eclipse it eventually)
Great feeling weapons and a decent community. Pick it up if you end up going VR, Its an instant purchase. PS the demo sucks (Its out of date and needs updated bad)
GORN
Smash a mother fuckers face! One of the games thats responsible for my blinds being broken, and my touch controllers having paint from the walls on them. Some will say its a dumb demo tech thing, others enjoy it a ton. Its cheap, its fun, you'll get your bucks out of it. Its kind of a work out game in the sense that you'll be swinging arms like crazy but its mostly a melee fighting game. Also has some new neat local multiplayer options.
All things said. VR is rad. Just expect to spend some money, and remember you spent 1000+ fuckin dollars, dont be a cheap ass with games. You'll never have any fun if you do.
Miss something? Lemme know! Might do some small game reviews. My library is starting to pile up so I need to get to the VR backlog before it turns into my normal steam backlog (70+ VR titles atm)
Glasses Wearer?
https://vr-lens-lab.com/