1) first see if you have SCSCI or IDE controller installed (or none?). Then get appropriate CDROM, any should do. I'd suggest connecting combo DVD drive it should be possible to read DVDs with some special software on Amiga (not sure, though)
2) not sure what do you mean, but
http://www.amiga-hardware.com/ might help. still, you'll have to open it to see whats inside.. :roll: (another option would be running excelent program called 'WhichAmiga')
3) '060 but it will cost you!!! (some 300$ or more if you're lucky enough to find it) it won't speed most of A500 games except maybe loading times but what speedup do you need?? maybe vector games like 4D sports driving or Zeewolf would finally run smooth. OTOH I doubt it, because they will probably need serious downgrading to run at all..
