I've installed Win7 64bit 4 months back that to install Kies....
Prior to that I had WinXP in my system. XP was installed on May 2008 when I bought this system...never a problem or BSOD.
I think, if u r playing safe with ur PC and use proper antivirus programs, u might not need to reinstall OS frequently.
I remember in my college days, due to a faulty RAM I had to install XP twice everyday, then install Java, then practice some programming...was a routine for me. (n00b of me as I checked everything for a problem but the RAM)
Once a frnd of me asked him to show how to install Java (we had just started Java then) and I started installing XP. He was so shocked...that he needs to format his PC to install Java. It took me couple of moments to make him understand that I'm not giving him half info or hiding any secret settings to run Java smoothly
