Vista Explorer.exe not working APPCRASH

Dear friends,
I 'm unable to boot in normal settings in Windows Vista Business 32 bit due to the following error noted from Event viewer.

Faulting application Explorer.EXE, version 6.0.6001.18164, time stamp 0x4907e242, faulting module unknown, version 0.0.0.0, time stamp 0x00000000, exception code 0xc0000005, fault offset 0x0001623c, process id 0xd20, application start time 0x01cba424d184c8e2.

Source:Application Error
Event ID: 1000

I have de-activated any new program installed in this whole month.

I 'm unable to get rid of this problem.

Please help.

Merry Christmas

You may have to try to perform these actions in safe mode if you cannot boot any other way?

Try a clean boot to help diagnose
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7

If that does not work
Try to go back, at least a week before the problem started, in safe mode (if necessary), using system restore.
http://www.vistax64.com/tutorials/76905-system-restore-how.html

If you can run a full anti virus scan and download and run malwarebytes after update at full scan.

Did it start after Windows updates?

Go to event viewer (type those words in search) then go to administrative secrion and look for errors about that time.

What were you doing when this happened? Is there any common activity during the crashes?

Here are some general guidelines
http://www.ehow.com/how_5192304_fix-appcrash-errors-computer.html