|If you start ok in safe mode, you might have a conflict with drivers issue, overlapping antivirus issues, and possible multiple firewall issues (though that usually leads to internet problems only). For driver issues, go to device manager and look for red or yellow warning indicators on any hardware, if any, delete from list, download updated driver, restart computer (it will detect and reinstall with newer driver. If you have overlapping antivirus programs, uninstall all but one. If you have McAfee and may be part of their latest screw up, go to their site for repair instructions, the uninstall Mcafee and get a better free AV program. If you have Norton, uninstall and get a better free AV program. Norton, McAfee and some security suites include a firewall, but so does windows, so disable one of them.|
Also go to Add/remove programs,and see if there is anything new that you did not install or you have no use for and uninstall, just to make sure your problem is not a newly installed program (including POSSIBLY a windows update gone bad)
You have to be a little bit crazy to keep you from going insane.