console or pc to build next ???

[daywane]

I want to mod a console into mame.
here is what I have been able to do so far.
1 ( I moded 3 ps1's  and  made the it might be nes disk for them)
2 ( made a vertical and a horizontal cab)( mamed pc's)
 butt ugly but work.
I did not have the funds to make them worthy of showing off , but that has changed.
( I will be bragging about them in a year)
I have a game cube ( we are nintendo fans here at my home) I think I would like to mod a console to mame and as many EMU'S as I can.
1. Atari 2600 ( and 800 (most of all)) (Xe or XL I don't care)
2. nintendo
3. nintendo super
4. nintendo 64.  ( I have not been able to get a working EMU of this going worth a darn) my PC is a 2.6 gig celeron,  512 meg mem , a 64 meg mem vid card.
5.sega master
6. sega genesis
7 . turbographix  ( one of my favorite)
8. game boy
9. game boy color
10 game boy advance
I have the ROMs. now what should I do? mod a console or build a PC? for the main TV?
I ask of you , can a xbox do these emus , a PS2 or dreamcast or game cube do these emus or should I build a PC for the main  EMU STATION ?  I am building a 1.2 gig Dell PC because I have most of the parts here) no hard drive or mem yet.