Vista Tutorial - Windows Explorer crashes when opening pictures

When I try to open a picture in Windows Vista on my new HP laptop, I get an
error message that says "Windows Explorer has stopped working," then it just
quits on me. Music files, Word files, movie files, etc all work. The only
thing I can't open are pictures, and none of them are corrupt.

Also, Windows Defender doesn't load right on Startup. It says that "Windows
Defender User Interface has stopped working" and won't load. I try to turn it
on through the Control Panel and it does the same thing.

Please help! If this can't be fixed, this will be the THIRD TIME I'll have
to return a computer with Windows Vista on it! I haven't installed anything
but pictures and music so far!

Your temporary application data (Windows Photo Gallery Index) has became corrupt. Thats the #1 reason for Windows Photo Gallery crashing a few seconds after being launched (as the timeout occurs on trying to open the index).

The resolution is to type into your Start menu's Start Search the following:

%appdata%

Once your temporary application data folder shows up, select windows photo gallery and delete it. Or rename if it your worried about losing information. Restart Windows Photo Gallery and you should be fine.

Ok, so I did the search for "%appdata%" but no "temporary application data"
folders (or anything sounding like it at all) showed up. Is there another way
of accessing the temporary application folder, and will deleting Windows
Photo Gallery help with the previously mentioned Windows Defender issue or is
that separate?