Old Purple iMac MAME Arcade Machine

Heres the plan:

1. Install some form of linux onto old iMac (ubuntu, DSL, whatever)
2. Find two sets of USB arcade style joysticks for super cheap, maybe with lite up little ball things.
3. Set up MAME-ness, make sure to include Ms. Pac-man, Galaga and Golden Axe. Maybe a street fighter
4. Find bigger monitor, hopefully 20"+ so that game look sweeter.
5. Build either and arcade cabinet or table to house everthing.
6. Figure out how to hook it to network so that it is easy to add games to.
7. Play the crap out of it

That is all. Any help, suggestions or insults please leave them here.