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Hi markysngc. Don't worry, I have two machines - one running XP on which I do all my work, and the (ex-) Vista one for compatibility testing (I'm a software developer), so trashing the Vista one was not a major worry for me - but it might be for anyone else!
I first tested Ubuntu running from the CD on my Athlon 64 with NVidia GeForce 7300. It was a great experience, and as I mentioned, the first time I made a change to the desktop, it detected my video card and downloaded and installed the correct drive.
I then thought to set up for dual boot, but as soon as I tried it , I could see that it looked kind of dangerous! The partitioning options that are offered don't match the ones in the documentation. So I thouht I would try VirtualBox instead.
Setting up VirtualBox was a breeze, and Ubuntu installed into it with no problems, but with everything virtualised, it was slow, I couldn't use my dua-monitor setup from within Ubuntu (although I could run it on one screen and see my Windows desktop on the other). Then, when I tried to open My Computer in Windows with VB and Ubuntu running,I got a BSOD from XP.