This could be caused by a bad/corrupted hard drive as pointed out by Chris or simply a lose/bad cable or a miss configured BIOS. If you could provide the make and model of your computer I could guide you through the problem.
As pointed out your laptop is already 64 bit capable, so there is no need to upgrade nor would it be capable if already 32 bit. To see if you are running 64 bit do this: Open start menu > Right Click Computer > Click Properties > Find in the window the 'System' section > under that find 'System Type' it will say '64-bit Operating System' if it is. Also as pointed out there is no Win 7 driver support much less 64 bit. I was going to suggest to try the 64 bit Vista drivers, however upon looking it appears there are no 64 bit available. A small side note is there is no need to run a 64 bit version of a OS unless your computer is using more than 4 GB of RAM; 32 bit versions work just fine.