OK, i didn't know how to get out of the first two options posted to be when i started the computer:

Continue with system resume
Delete restoration data and proceed to system book menu

Since the first one didn't work, i figured i could try the second one. And what happened? it proposed to do error checking (or check disk or something). I let it go through it, thinking it could not hurt and might reveal something.

I didn't have time to see the result, and the computer started normally, all by itself. Should i still go through that checking with the CD booting or can i check whatever needs checking from the PC itself? And if i need to book from the CD, do i still need to go through the BIOS?