You do not need control -alt-delete to do this one:
http://www.thewindowsclub.com/windows-explorer-exe-does-not-start
This simply allows you to make sure your explorer.exe is in the registry where it belongs.
(You get to the registry editor by enetering "regedit" in the start/run box much like typing in msconfig)
You should try this by going into safe mode.
WHILE in safe mode, scan the computer for MALWARE and set the C drive/properties/tools to do a check disk at the next startup as well so it can fix registry errors.
I just did this last night on my nieces computer using same method.
I think it wqill work for you,
micro....
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