This is definately the wrong forum for this, but since I know everything anyway...

Go to tools/options/maintenance tab.... there's a "store folder" button. Click on that and it'll tell you where your outlook stuff is stored. Just take that entire folder and copy it. When you reinstall outlook later, point the store folder to your backed-up one. I would suggest keeping these folders on a seperate drive premenantly as it's easier to reinstall for future re-installs of windows.
Note that if you have multiple users, you'll need to switch to each user and repeat the steps above for each one.