Mac 10.5.8... programs keep crashing, mac freezes

Question

Hello!
I am running a 10.5.8 and am having a boatload of problems with my laptop at the moment. I can't remember exactly when, but a few days ago my laptop began to freeze whenever I would start a web browser (doesn't matter which one). Then I noticed Last.fm would crash as soon as I opened iTunes. Been trying to fix Last.fm, reinstall, uninstall, reinstall, whatever. Doesn't help. So I've tried searching for viruses... nothing. Verified and repaired the disk. Nothing. Running in safe mode doesn't help much, as Safari as crashed multiple times just in me trying to type this.
I'm running low on options. After searching and searching, it seems the only option is to do an archive and install. Here is my question (be gentle)..... am I going to need to back up my files before I do this, or is it going to save all of those for me as part of the archive? I want to know if I should do that anyways before hand.
Thank you.

Answer 1

If you have an external disk it is always best to backup, erase the disk and do a clean install with the original DVD.
I prefer to use Carbon Copy Cloner for the backup but in many cases simply taking a copy of users' Home folders with the Finder is adequate. Check that the backup contains all data and is readable before you erase. Better still have more than one backup.
It is best to avoid the temptation to import anything from elsewhere during the install because this so often reintroduces the problem.
Make sure you know your network settings.
Good luck.