long story short, i got data execution prevention alerts, so i posted in the malware forum. turns out there was no malware involved.
RKinner (thanks again! :-) sugested my hard drive might be dying.
i managed to burn the bootable diagnostic cd, which corrected 3 errors, and then my hd passed the diagnostic test.
i used the acer erecovery hidden partition to return my laptop to its factory settings. i only installed avast!, firefox and adobe flash, and had no problems for a month.
then i installed some of the other programs i use frequently, and the same evening i got 2 data execution prevention alerts, windows needs to close this program: windows explorer, plus dr.watson's postmortem debugger.
these programs are:
foobar (media player)
on a sidenote, most (but not all) the data execution prevention alerts pop up when i'm using windows movie maker, or shortly afterwards.
to be honest, i've gotten used to them. i "unfreeze" my compu with windows task manager, and go back to work. but i would appreaciate it if you could help me at least understand why i get them, if not get rid of them.
ps.i'm not entirely sure i'm posting this in the right forum, if not please move it, or redirect me appropriately.