Okay - it seems the laptop is back... though all I did was reinstall windows. I had it checked by a repairshop, and they couldn't find any hardware problems in their diagnoses. They said it could be from having older 32-bit programs/plugins, clashing with my windows 64-bit system. As I do (or, did) have many older music plug ins for composing, this may be true...
I am reinstalling programs now, including RPG VX. Hopefully the laptop keeps working, though I think I won't install my music programs just yet, until I've tested them on another platform - to be sure.
Thanks for waiting, everybody... please be a little more patient. I am cautiously optimistic that the laptop is okay now...