Seems you have the RtlpWorkerCallout bug (Can't be sure without seeing the other crash reports) that seems to be malware related from the very little digging I have done from your crash report (I am not to familiar with FireFox other then fixing it for co workers). Some sources are here http://support.mozilla.org/en-US/questions/928020 (Matches your crash report and symptoms).
So the signs are pointing to you being infected. You have multiple options from here. You can start using tools to try and remove all malware from your system or you can do a fresh install (Probably the best option and least hassle). If you do a fresh install I would recommend first scanning all the files you are going to backup to transfer over to the new install of your OS just to make sure they are not infected also (There is still no 100% guarantees even with multiple scans).
@Fredbill u haven't tried linux that's why u hate it...windows is shit and for newbies......virus...shit......try linux and u will fall in love with it...it's wy faster.....no defregmenting ..and so much more