Ultimately the question is "What do you want to do with any computer"?
For any kind of internet browsing (which, considering you've already posted here, you may have sewn up already) at high speed, a network card is a must. The A3000 has SCSI built in so you *shouldn't* have too many issues getting mass storage working - it'll probably come with some order of hard drive; if not, well, what's $10 or so for a 4 gig HD?
As to what colors you should expect, the A3000's were all ECS equipped so 16 at higher resolutions, 32 or 64 for low res.
Myself, I'd recommend you get yourself a video card but that's just me.
