"Sounds like a hardware problem, but we can diagnose that pretty quick. If one of these solutions fixes your problem, there is no need to move onto the next:
First, have you tried the Last known good configuration? You should be able to choose it on the same menu where you can pick safe mode. It will use the last settings that worked successfully.
If you have a Vista DVD lying around, boot from it and try a system repair.
If you've got any spare CDs lying around, try burning a Linux distribution such as Ubuntu to it and try to boot up. The latest Ubuntu should come with ntfsfix which will fix common NTFS errors. In the Terminal (Applications -> Accessories -> Terminal) run ntfsfix /dev/sda1. If that gives you an error about the device you probably have a drive connected via IDE, try ntfsfix /dev/hda1. You haven't indicated if you're dual booting so these device names should work.
If none of this yields anything, or you get errors trying Ubuntu, it may indicate a hardware problem. After being left on over night and becoming hot, it could be a few different things. There may be a problem with one of the motherboard's capacitors, memory, or even an issue with the power adapter among other things. A very hot laptop is usually related to heat dissipation problems. If it's under warranty still, you may want to take it in to have it looked at. If not, and you're comfortable with opening it, try and clean out some dust."