I have an original SW I picked up that was gutted. I added all the parts I collected over the years and rebuilt it sans boards and monitor. It's running MAME booting right into SW, but if I open the coin door and hit a switch, I can play ESB, ROTJ, Firefox, Paperboy, and STUN Runner as well.
As far as monitor goes, I just put in a 19" Dell CRT I picked up from Craigslist. I'm not running a special vector version of MAME or anything. You'd be hard-pressed to see a big difference if you're a casual gamer. If you're a hard-core vector collector, sure, but the CRT looks great. I decased the monitor and shoved it into an arcade monitor cage I had from a broken Wells-Gardner. CRT all the way.
How big do you actually WANT to make this cabinet?