apps hang when opening/saving

Maybe 6 months ago apps started to hang/freeze whenever I opened or saved a file. Sometimes the hang occurs immediately after opening/saving but other times it doesn't hang until after a few open/saves--it doesn't matter which or in any particular order (open first then save, or vice versa).

First I thought it might be Firefox since I noticed it happening there exclusively but that was just because I tended to only use that app for long periods of time (leaving it open with many tabs). But then I tested other apps and, sure enough, they started hanging too. Now, I've been using File-Ex (a shell extension hook--whatever--that handles open/save dialog box resizing, recent/favorite directory memory, etc.) for years with no problems like this. But I tried disabling that and it doesn't make a difference with the hangs.

The only thing I can think of is it might have started after XP failed to upgrade to SP3 but I believe the hangs started before that.

I've also tried: chkdsk, defrag, checked shell extensions but can't find one in the ~6-month timeframe that could be causing this, no dead network shares.

Any ideas? Very annoying having to end-task apps all the time after opening/saving a file...

 

Sorry, didn't see the moderation note until I tried reposting a new thread--and, of course, since neither thread appeared I couldn't delete it, so...