I missed the post where you mentioned it's a laptop. I've dealt with a few of them that were crippled because of HDD trouble. Assuming you didn't pop for the SSD, then a stumbling hard drive might well be the culprit. Back up your important info, run chkdsk, making sure that it reboots and runs in the pre-windows environment, and in 4-8 hours, I bet you're golden. Hard drives don't handle the laptop life too well, and eventually pick up quite a few bad sectors. Trying to access data from a bad sector will hang the thing for quite a while. Chkdsk with the surface scan will find the bad sectors and mark them unavailable.