I can't tell you the exact method of uninstalling, but some tips for you...
- Back up your playlists prior to uninstalling! Backup any rules for customised smartlists.
- Make sure that all your tags are up to date so that when you do a re-import, you get your library back to where it is now!
- Keep a note of any customised fields that you have.
- Back up any customised visualisations that you might have.
The reasons that I suggest doing this instead of backing up and restoring your library is because (as was my experience) over the various builds of MC, the library has changed slightly and so while not strictly corrupt, there are parts that don't work as well as they could!
When starting over again, make sure that you create your customised fields before importing.
Also be aware that importing playlists tends to make a bit of a mess, as far as organisation goes, so depending on how you've organised your playlists, you may want to make a note now of where they belong!
Hope this helps!
P.