I think no matter what router you purchase will work fine with any computer. I'm sure setting up any kind of router will be just as to setup as an Airport router. I have used Dlink and Linksys routers with my macs without a sweat. As for performace, distance and speed, I would recommend any G wireless router, but it's hard to judge one router over the other, because everyone's experience is different, even with the same router. I would try cnet.com and look under reviews and see, if you can find a good recommended router there. Right now, I'm using a Linksys WRT54GS; I'm pretty satisfied it with.
That linksys that MacMan just recomended is a very good router. Probably the best one out there that is not some professional Cisco. It's very reliable and secure and has good wireless range. I have been using Linksys since I first got DSL 3.5 years ago and never had a problem. The Firewall in that Linksys is very good also with full SPI Firewall.
I use the Belkin Pre-N router, which CNet gave rave reviews (bettern than DLink and LinkSys). Needed no software install, just tell airport to go find it. Its working wonderfully, and at $114 at Buy.com its a steal.
I've got the Linksys Wireless G Router, and I love it. It was very easy to set up and the range is great. I have never had any problems with the router, its always reliable. Plus where ever I am in the house, I always get great reception. This is my second linksys router (my last one being wired), and I'd strongly recommend it.