There are several recent threads on this... do a search to get more answers. The Asante is extra Mac friendly in supporting AppleTalk... but they will all work fine with Macs, in general. The g devices' extra speed is worthless for accessing the Internet; but if you'll be communicating with other computers on your LAN, the g standard may be well worth it.
My suggestion: look for bargains. I just got a SMC g router for $40-somethin' at a CompUSA Grand Opening. And for another network where I needed a print server for an old laser printer, I chose the Asante with built-in print server (making it a steal for my needs, especially with the rebate).
HTH.
P.S. This is in the wrong forum... so do the search in the Networking forum... you'll find tons on wireless routers and g vs. b there.