Windows Explorer Hangs Randomly

I have suddenly started having a problem with the Windows Explorer Folder Tree randomly hanging up with no error message. I then have to end WE in Task Manager. At first after returning to WE all that would be shown was "Libraries", but since I don't use Libraries, I disabled them. Now all it will show is Desktop and Favorites, so I can't get to any other files on WE, or, more importantly, drives.To get rid of the situation I have to reboot after which I sooner or later have to go through the whole process again. I am using the following: Dell XPS 8300, WIN 7 Pro 64 bit, intel i7 processor quad 4, 12G RAM, 1T ROM.

Occasionally at the point WE hangs my file thumbnails become blank and sometimes even the non-system icons on the Desktop also become blank. So far the System Icons (Network, Computer, Recycle Bin, etc) have never blanked. I can usually get into the Tree without a hangup in other programs when using File. Open.

I have run Norton 360 and Malwarebytes (full scan twice each) anti-virus, sfc /scannow, checkdisk, Tuneup Utilities and the complete Dell diagnostic suite. None shows any problem. It is almost resembles a memory problem, but with 12 gigs of RAM that shouldn't be likely.

At this point I do not want to do a System Restore if at all possible.

Any thoughts will be appreciated.

Addendum: In trying to start in Safe Mode I have discovered that F8 won't do it, and the "RUN" option on my Start Menu has disappeared, so I can't use MSCONFIG. Don't know what that all means.

Still have not solved this problem, even after using several full virus scans, Fixit, starting in Safe Mode and creating a new user. System Restore cannot be done as the older restore points have disappeared. I have a Dell Win 7 64 installation disk. Can I reinstall it directly over the old installation or would that cause more problems than I have now.

I'd try to System Restore to before you disabled Libraries and made any other tweaks, then leave them alone. They don't interfere with anything and you get into trouble when you mess with things you know nothing about.

Likewise Norton 360 is a huge overweening bloatware imposed on the first featherlight OS, so I'd use the recommended free lightweight Microsoft Security Essentials with the Win7 firewall and uninstall Norton.

Similarly TuneUp Utilities will only cause problems since Win7 is too lean to tolerate that kind of tweaking which went out with XP and fat Vista.