Windows 7: explorer.exe failing to open startup files and folders

starting here - please redirect if I need to post elsewhere.

my windows explorer file is in continuous failure. not sure if a corrupted registry or not

there is no blue screen of death, no error message just a failure to open items in the startup menu and occasionally a menu item will be dropped from the menu.

i'll get a blank window and the infamous circle icon attempting to open something like on a very slow computer

all browsers and programs run fine that are already opened

so my temporary work around is to use task manager to end the explorer.exe process

this wipes out all desktop icons and the start menu

again all other open programs continue to function normally

then while in task manager, I'll click on "new task" in the applications tab and restart explorer.exe

then everything functions well - I can open and access folders and programs - for a while

I can also accomplish by restarting my computer but using task manager is faster.

I've not timed how long before explorer fails again or what triggers it.

I've searched the internet and haven't found anything close to this issue.

Can anybody point me in the right direction?

First thing I noticed. From you Specs.
Antivirus windows defender
Windows Defender is not as good as it needed to be to protect your system. I recommend Microsoft Security Essentials.

http://windows.microsoft.com/en-us/w...tials-download

After installing it and updating it I would run the long (complete) scan.
Your computer could be infected.

You could also run this Tutorial from Brink.

SFC /SCANNOW Command - System File Checker

This tutorial may help .... Troubleshooting Explorer.exe Crashing Issues