Very weird problem with acer laptop

I am having a very strange problem with my Acer Extensa 4630z laptop. I dont know how to explain it at all anymore so I'll just explain everything that has happened and hope someone can help me make sense of it. I am trying to install windows 7. The first attempt took about three hours to complete, which seemed very odd, but it never gave any errors or crashed or anything. But when it finished and rebooted for the first time it froze on the windows is starting screen. When i rebooted in safe mode it stopped at a file called disk.sys. I tried installing it again just in case. I let it go overnight and in the morning it had managed to boot into windows. I thought everything might be fixed so I started to install programs and set it up. But the first time I restarted it froze on the windows is starting logo again. In safe mode it was once again disk.sys. I ran some hard drive diagnostics and none of them finished normally, some crashed while others said they could not detect a hard drive at all, so I thought it might be a hard drive failure. I tried a new hard drive and got the same result. I have tried changing BIOS settings. Same result with AHCI and IDE modes. I also tried installing from a USB drive instead of a dvd with the same result. I tried installing windows xp and it froze at the setup is starting screen. Oddly enough linux installed without a hitch and is now running, but seems very sluggish. Also, when the computer first turns on now a bunch of different colored lines pop up after the first fewloading screens then the screen shuts off, coming back on a second later and it boots up fine. Linux is just a temporary solution though. I still want to run windows 7. My next thought is to flash the BIOS but the only thing acer offers in that regard is a windows program, which obviously doesn't help me so I'm unsure of how to go about it. I'm sorry to write what feels like a whole damn book about this but I dont know what else to do. This is getting incredibly frustrating. Any ideas, no matter how crazy they might be, would be greatly appreciated. I'm willing to try just about anything at this point.

I just ran memtest 86 from the ultimate boot cd and it didnt find any problems.

Only thing I can think of left is to breadboard it. Remove components and start adding them back until you find a config that doesn't work - then you should find where the problem is.