Q: Unable to download new version of ITunes.  Unable to locate serial number on laptop.

I tried updating my Windows 7 Home Premium ITunes to the newest version and received an error message.  The majority of the products on my laptop are Microsoft.  However, after contacting them, they stated that I had to contact Apple since they did not support this product.  How do I uninstall and reinstall ITunes?  If reinstalled, will all previous data, music, etc. be lost?