That's often the work of nasty shell extensions that insert useless and shameless advertising into the desktop context menu. I'm going to start pointing fingers at Intel and NVidia. When either are enabled I get a delay in opening the desktop context menu. Fortunately it's easy to fix by removing all traces of the shell extensions with Sysinternals Autoruns.

Yeah likely Nvidia, forgot about that (I still remember recently having to disable nvidia.sys or something similar from startup as it would prevent group policy from applying on certain PC's - it's a bug they've had for years, ridiculous).

Amen, brother. Unfortunately this won't be fixed, ever, due to various reasons I won't go into.

Expressionless  Yikes.  Are you an MS employee or is this NDA-specific?  It really is Windows biggest fault IMO, so that sucks if it can't be fixed.