Thank you all for your replies. I'm currently reading a book about freshwater aquariums, so hopefully it will help.
About heating the new tank, though:
If I put the betta in it before I turn on the heater, won't the gradual heating of the water be OK for acclimation, or do tank heaters heat the tank up very fast?
Thanks again for your help! I can't wait to set him (still haven't named him) free in a 10 gallon. ;)
Oh yeah, about the tankmates, I was thinking about the glofish...any suggestions there?