Windows 7 32bit Not Working?

I have a NB550D with windows 7 home 32Bit installed and but i am having issues with it. I usually put it to sleep all the time as i use it for school. I went to use it 2 days ago and it started to become REALLY slow. The hdd light was on all the time and doing anything started to take a very long time. It ended up blue screening with something up the top with irql not less or equal message up the top but before i could read anymore it restarted.When it starts up, it prompts for my password, and i login. It then sits on the Welcome screen with the little circle spinning for ages. it ends up with a black screen with the cursor that is moveable for about 10 minutes and then it freezes. The hdd light is on the whole time.

It is booting into safe mode so i decided to install SP1 to see if that would cure it which it did... for 1 day. It has stopped working again today with the same symptoms but instead of it sitting in welcome screen for 5 minutes it sits there for about 30 seconds and then goes to a black screen with the cursor. It appears to be loading something because the cursor has got that little spinning thing and then after a while the task bar comes up. It is responsive to some degree but the background is nowhere to be found. I can move the mouse right up until 2 seconds before it reboots. there is no warning as to when it reboots, it just goes blank and then the BIOS logo appears. It appears to be trying to load something faster than the HDD can cope and then it crashes. It still boots into safe mode.