Program Not Responding Issues

I seem to get more program not responding error messages as time goes on. In the last couple of days some of the programs have been Jasc Photo Shop, msn messenger, msn.exe , gcasServ.exe, and teatimer.exe. Sometime I will get the "End Now" option box, but a few times it just seems to lock up at this point. I then have to gone to Alt-Ctrl-Del and then tried to do a restart. The last time I did this I noticed two entries for Dumprep.exe using a large amount of resources...the memory use was shown to be 100%. Normally, I am below 5, like 2-3%. Then the "Windows is Shutting Down" screen hung up and I had to hold in the power switch to get the thing to turn off. Up till lately the End Now button seemed to do the trick, and it does on occasion, but these last few episodes where it seemed to hangup make me wonder if something else is wrong.

 

Otherwise, things appear to run normally, albeit slowly, since I stubbornly stick with dial-up. Virus and spyware scans do not show show anything, and there doesn't appear to being anything in the HJT log that shouldn't be there. Any suggestions where I should look or things I might check.