Are you using the drivers given by the Windows 7 installer and quickly updated via optional Windows Updates, or are you still under the impression that this is XP and you need to import drivers for no reason to replace the ones which MS spent millions to get into the installer and via Updates? Do not change the drivers given by installer or quickly updated via optional Windows Updates unless there is a confirmed performance reason to do so.
If you have done so, try to System Restore to before problems occurred or you changed out the drivers. System Restore
Otherwise the appcrash issues are troubleshot by googling repeat error (text and ID#) in Event Viewer>Admin View to find the cause and see how others have resolved them.
Likewise study the Performance log on Advanced Tools page accessed by clicking the WEI score link at Computer>Properties. Look for cued issues at top of Tools page, Generate a System Health Report.
Type "problems" in Start Search box to look for solution to problems sent and not. Windows 7 is interactive in this way.
Run SFC /SCANNOW Command - System File Checker
and then if necessary a Repair Install
If all else fails, wipe the HD of all code to try a clean reinstall using these tips to get a perfect install: re-install windows 7