Windows 7: Programs crashing or not loading correctly

I've had problems with programs loading on my system.

Sometimes when I restart I get a Run DLL message saying "there was a problem stating c:\windows\$UninstallMTF197$\dhgbo.dll access denied"

Sometimes when a program crashes it tells me microsoft will inform me if there is a fix. Other times it prompts me to send a report of the error. When I check the details this is what is displayed:
Files that help describe the problem:
C:\Users\Joshua\AppData\Local\Temp\WER1B0E.tmp.WERInternalMetadata.xml
C:\Users\Joshua\AppData\Local\Temp\WER2FA8.tmp.appcompat.txt
C:\Users\Joshua\AppData\Local\Temp\WER424E.tmp.mdmp

Read our privacy statement online:
Windows 7 Privacy Statement - Microsoft Windows

If the online privacy statement is not available, please read our privacy statement offline:
C:\windows\system32\en-US\erofflps.txt




I have also had trouble installing an update from windows upon shutdown. It has been attempted twice and gives an error message that is currently unavailable to me.

All of these problems began suddenly and seemingly all at once. I have recently uninstalled Norton AV and installed Avast AV. Are there any known compatibility issues with Avast?

I have no idea what is going on but it's pretty far reaching and debilitating. Any help finding out the problem and possible solution would be greatly appreciated as I am currently unable to reliably run many programs that i have used frequently. These programs include firefox, rosetta stone, calibre2, shareaza, realplayer/downloader, etc.

I've already run a sfc scan with no problems.

Thank you,
Joshua