A couple weeks back my dual boot system went bad. I have had WinXP on my computer for many years. I then decided to try Windows 7 RC. I took another hard drive, and made a fresh install of Windows 7 and installed it as Hard Drive #2.
After a few weeks of successful dual booting (using either WinXP or Windows 7 by selecting which one I wanted to use upon booting the computer), the computer though a tantrum and the Boot Loader got corrupted during a dual boot load of WinXP.
Long story short, I finally got it running again, I took my WinXP disc and loaded it over my original install. Yes, I know you can get into boot load files and check the code and chage it, if need be, but I chose just to rewrite and re-install WinXP over gain, no harm done to any of my other files, it worked fine.
I have no idea how the boot loader got screwed so bad. I have since retired the Windows 7 Hard Drive. But, I will probably buy Windows 7 when it comes out, right now I am low on funds, so I may not be able to take advantage of pre-order prices. I have done upgrade Windows version int he past but was always much happier if I just bought the full version. Besides, if you just buy the upgrade, then you nee dot keep the other version, and cannot sell it, because it will be needed for installs and re-installs for the upgrade version. I want Windows 7 because I want higher performance in my games and sims I fly.