Since it is when your regular desktop shows up, but it does not happen when you startup in Safe mode, I'd suspect the video driver.
When in Safe mode, remove your current video driver. Boot up to your regular desktop, which should now be in VGA mode (all video cards have a default VGA mode, when you don't have a driver installed).
If the desktop is now not frozen then that helps prove it was your video driver being the problem.
Then go to your video card manufacturer's website (or your motherboard/or computer website if the video circuits are integrated into the motherboard) and get the latest video driver. Make sure you are not getting a 32bit driver if you are running 64bit OS, or vice versa.
See if that fixes the problem.
My computer freezes as soon as it reaches the desktop home screen. Clicking anywhere one the screen or pressing any button on the keyboard has just no effect whatsoever. I mean there is no response at all and I end up restarting the system. Although it works fine in Safe Mode (with the audio and graphics disabled, which is quite and irritating at times). My system configuration is as follows:

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