i have to agree with these guys...sounds like a great idea...if you are filthy rich. you are going to have thousands of dollars into this project the way you have laid it out. you would definitly be better off building a cabinet based off of a console. as it looks right now, virtua fighter 5 is available for both the 360 and PS3, and street fighter 4 will probably be avialable on both as well. but from what i read, tekken 6 will only be available on the PS3. as for interfacing the controls, i know that x-arcade sells adapters for their encoder to connect to the PS3...they currently don't have one for the 360. i dont' know if any other encoders will connect to either of these consoles. even building a cabinet with a decent sized HD monitor and a PS3 will not be cheap to build. just be aware that this hobby is much, much more expensive that you could ever imagine it would be. so plan out what you will think it will cost, and be prepared to spend double that by the time you are finished.
i was about your age when i started putting plans together for an arcade cabinet. of course this was 1996, so I wanted to build a cabinet that would play Mortal Kombat 3/ Street Fighter 2. i was drawing up plans for the cabinet for weeks, at that time i was planning on using a SNES to run everything. as it turns out..when you are 16 and have no money, and very little space to call your own..it just isn't very practical. it was about 10 years later until i finally realized i could actually build my own cabinet. by that time i was 26, engaged to be married and we were renting a house. i had plenty of room for a cabinet, I had a much better understanding of computers (I'm an IT consultant now) and i already had an x-arcade joystick that i used for my xbox and dreamcast. and now MAME could easily handle the MK games that i wanted to play, which wasn't the case 10 years earlier.
my point is that you should take the time and plan this out, and be aware of the cost. it is really cool to have an arcade machine, but at 16 years old..there are probably better things you could be doing with your money. so be patient and it will all work out. If you already have a 360 or a PS3, i'd probably start by just building a control panel and using that with the TV...you can do this in baby steps if you need to