Well... if compability before everything else is what you're after then 030/50 is the best you'll get.
ROM3.1 is never bad... it's a better rom and of cause lets you install OS3.5/3.9 if you like.
OS3.1 or 3.9 is a question of taste... I have different on different machines as I see fit. 3.9 uses up more power but gives you more eyecandy while 3.1 is dull but also faster (and if you like more stable).
I'd never recomend a 040 board for anyone... 060 boards runs alot less hot, are more compatible and gives you much better speed for the extra $ you have to spend when uppgrading from a 030 anyway. With a Blizzard1260 (and probably others aswell) there's a fallback mode so if a perticular game refuce to work under 060 you can sacrifyse your fastmem and try run it under 020 with the use of a key. :-)
