FP crashing in both IE and FF; reinstalling not helping

Running Windows 7 64-bit on a 2-year-old Dell laptop (Studio 1745).

For the past year or so, I've been having the following problem: every once in a while flash player will decide to stop working and will crash in both IE and Firefox.  The browser freezes up for about 30 seconds, then the "The Flash Player has crashed" "send a crash report" message comes up.   My standard solution for fixing this was:

-run stand-alone uninstaller

-delete everything in appdata/roaming/adobe

-delete everything in appdata/roaming/macromedia

-delete c:/windows/syswow64/macromed

-reinstall current version (separately for each browser, sometimes as a plugin for FF)

Most of the time this would fix things; occasionally I'd have to do it two or three times but eventually everything would work.  I could watch youtube, play games on kongregate, and teach an online class that uses flash.

It crashed this morning (while using work gmail, something I do every day) and reinstalling isn't working.

I have tried a few things.  I was able to see the animation on http://www.adobe.com/software/flash/about/, and from here I was able to disable hardware acceleration.  That did not help.  I thought Firefox might be doing something weird with it, so I reinstalled firefox, no luck.  I tried instead installing a debug version: 10,2,159,1.  This still crashes things.  I haven't yet tried to roll back to, say, Flash Player 9, but this seems like a pretty extreme solution as something else is clearly wrong.

Any ideas/thoughts would be welcome.  Memory issue? Video drivers? I'll try about anything at this point.

Thanks!