My main working computer is Mac G4, 1GHz processor, 2 GB RAM, ATI Radeon 9800 Pro, 3 internal hard drives, a PCI card for the bigger hard drives and another for extra FireWire/USB2 ports. I've modified the power supply and replaced the fans with super quiet Panaflos.
I also have a nice little AMD based PC with 1GB RAM etc. but prefer the Mac for several personal reasons. The operating system, OS 10.4.2 aka Tiger is a bit more elegant than XP. I can recover from 'issues' more readily than Windows. Partly that's just familiarity but there is no Registry to get hosed. Perhaps the biggest difference is the online experience. No viruses, no spyware, no ad ware still and OS X has been around for well over 4 years. No Nortons, ZoneAlarm, Ad-Aware, Spybot needed.
Don't get me wrong, my little Windows box is a good machine. XP Home has not crashed once in 9 months, apps launch instantly (it seems compared to the Mac) and it has recognized all the hardware changes I've made without making a big deal out of it, as older versions of Windows might have.
Frankly, if I were a Windows user thinking of migrating to Mac, I would seriously consider waiting until the Intel Macs are released in a couple of years. If you got a tower, you could add a few hard drives, use one for the Mac OS, one for Windows, and one for a scratch disk. I believe that is the strategy I'm going to pursue.
Oh about the right click business. I've been using Intellimouse Explorers for years and have all the buttons configured. I couldn't get on without them. One button mice pfffftttt!