my xp had a couple blue screen episodes that caused me to get another hard drive. I decided to go with vista at that time--April--and had more blue screen the first week then with xp. Long story short my pc keeps crashing and I want to try windows7. I need to get vista off but add/remove doesn't list it as a program I can remove. I've tried three times to install windows7 using the custom install but vista seems to be holding on by it's fingertips and the install fails. How do I get vista off and install windows7?