1. Tosh M205 - Most likely a bad stick of ram. But a replacement stick at a local shop (hell, get a bigger stick - not a bad time to bump up, ram is cheap). The Portege M205 has two ram slots, so check each in turn.
2. The "SM Bus" controller (system bus). This is a part of the AMD chipset (AMD M780V) on the motherboard. Unfortunately, I don't think there is an XP driver for this chipset.
3. Your choice of "broadband" wireless provider depends heavily on your location, but you'll probably be choosing between two providers - AT%T and Verizon. AT&T's 3G wireless (HSDPA) has a pretty limited rollout so far compared to Verizon's (EV-DO). Check the service maps to figure out which one wil best suit your needs- AT&T - http://www.wireless.att.com/coverageviewer/ Verizon - http://www.verizonwireless.com/b2c/CoverageLoca...