I have tried out four (thanks to Circuit City's new return policy) wireless G routers. I rank them in the following order.
1. Linksys
2. D-Link
3. NetGear
4. Belkin
I have a two PC Desktops

and a G4 iBook (airport extreme), setup for both was very painless. The PC was plug and play and the iBook recongized the new network right away with each router.
Linksys---The range is awesome, about 60 feet and through two walls I have full signal strength. This is the one that I ended up keeping. The main reason why I chose this one over the D-Link and the Netgear was simply it worked better with my current 2.4 GHz cordless phone (Panasonic). I didn't have any problems with signal while using the phone and the phone was clear of static.
D-Link---Very nice router, the range was almost as strong as the Linksys, but the router significantly slowed down when using my cordless phone. I lost almost all of the strength of the signal and the phone had a lot of static.
Netgear---The range was very comparable to the Linksys if not slighty better, but almost everytime I used the phone the router would reboot causing me to lose the signal on both my wired and wireless connections. I tried two different Netgears, just to make the sure the first one wasn't the problem. Needless to say I had the same problem with the second. The times that is didn't reboot, the signal went way down and the phone had a lot of static.
Belkin---I don't recommend this to anyone wanting to use a wireless connection more than 20-25 feet away from the router. When I was close to the router it was perfect, no interference with the cordless phone either.
edit: BTW......All 802.11g routers should be backwards compatible with 802.11b. All of the routers mentioned above had options similar to g only, b only, or b and g.