iTunes and iPod Touch Problems (A few Questions about upgrade)?

I have a couple of questions:

I upgraded with the newest iTunes software and ever since keep getting “iTunes has encountered a problem and will shut down” messages. If I completely uninstall this from my PC and download it again will I lose everything in my library?

Secondly, I have an iPod Touch. After I downloaded the new iTunes it asked me if I wanted to upgrade that. It is the new special upgrade for 9.95. I did that and got an error again from iTunes and it ruined my Touch causing me to do a factory restore. I finally got the upgrade on and the only new icon was the App Store. Should there be more icons from this AND if I restore again and re-download iTunes could I still use this upgrade or will I have to pay again?

Detailed answers from experience Apple and iTunes users are welcome! I always pick best answer too if that means something. Thanks!
Sorry, forgot to add that I have a ton of stuff imported into iTunes from CDs. Will this still stay on it if I completely uninstall and reinstall? I know anything that I purchased will. Thank you for the help!