Advice needed

I've recently had some problems where my computer will crash randomly for no real reason. I'll be reading an email or something and it will flash the blue screen of death and restart. A while ago I had this problem where it would continually do that and not allow me to restart. I ended up reformatting the computer just to save myself the trouble of figuring out what was wrong. It seemed to fix it but now this is happening every so often. I have my HijackThis log attatched...basically just wondering if anything looks strange in it.