We purchased a Netgear RangeMax Dual Band Wireless-N Router with our new Dell desktop. When I tried to hook up the router to connect my two computers, I realized that my modem is not compatible. My modem is provided by my cell phone company and is connected to my computer via a USB port. No place to plug in the Ethernet cable from the router. I would try connecting the two computers to gether with a crossover CAT5 cable, but one computer has Windows XP and the other has Windows Vista, and I was told this could create problems. Can I still use this router wirelessly? Or can I purchase an adapter? All adapters that I looked at have male USB ends on them. My modem also has a male end. Can I use a female to female gender changer to rig this, or will it cause problems? Or should I just purchase a whole different type of router? Not sure what kind to get or what to do.

What type of modem is it, ADSL or DSL? What's the model number of your Netgear router?
You need the right type of router for the right type of phoneline that you're on - they're not interchangeable.
You will be able to use both computers wirelessly, you don't need any cable whatsoever if that's the router you choose. The Windows on the machines is, to all intents and purposes, irrelevant.