Program startup problem

Hi,
I've searched the forum but haven't found any similar posting.

I can't start any program (e.g. taskmanager, IE) after a system startup. The mouse pointer turns into the "waiting circle" and nothing happens. If I open the explorer (which is the only thing I've managed to start) the windows opens but with the message ontop saying "not responding". The only way out is to press the on/off button for some seconds.

I think I found a workaround and that is to first startup in safemode and then reboot. It has worked for five times.

Since it works after my workaround do I think it's not related to the HW. For me it seems that there is something in the system not starting up properly. Is there a way to find out which part causes this problem ?
I've also checked the logfiles and I can't see anything strange.

System configuration
Dell XPS M1530
Vista Home Premium + SP1

Thanks

My thoughts are that you may have some sort of virus on your system...
Try using Malwarebytes.org or or Dr.Web CureIt! – download free anti-virus! Cure viruses, Best free anti-virus scanner! and see if they come up with something.
Otherwise try repairing installation

In safe mode everything work fine?

1.Diagnose your system by using Reliability Monitor Reliabilty Monitor

2.If everything in safe mode work fine and there is no errors in Reliability Monitor try
Clean Boot procedure How to perform a clean boot procedure to determine whether background programs are interfering with a game or a program that you currently use

An update

I scanned for malware and didn't find any.

Flavius, About my "workaround". When the problem occurs I shutdown the computer the hard way by holding the on/off button for 5-7sec. Then I'll starts the computer and make sure to go into the safemode. The computer works fine and I performe a controlled restart. When the computer are back in normal state it just works fine.

I can't see any thing logged in the reliability monitor correlating to the problems I see. I will now try the Clean boot procedure.