Electronics

[LAllyR]

I'm upgrading my desktop computer with more RAM & Windows 7. I'm going from 1G RAM to 4G & I will be going from Windows XP to Windows 7 Home Prem. My question is in regards to which Windows 7 product to get? I have looked up the software on various sites & see that there is the full version, the upgrade, & then some of them say "System Builder" which I don't understand what that is? My plan is to format my HD so I can get a fresh start & get rid of a bunch of things I don't want on there. I'm pretty sure I'd just get the upgrade & load XP 1st then 7 upgrade after the format? But, do I need to buy the one that says System Builder? I'm not really interested in getting Windows 8 until it's been out longer & the bugs (that I've heard about) have been taken care of. Any advice would be greatly appreciated. Thanks!!