i will load it up, then once its loading it says the zune marketplace has got a problem and has to be closed down. if i reinstall the zune marketplace will all my songs go away.
I'm guessing you mean reinstall the Zune software right? If you reinstall the software, the actual files will not be deleted, however you will lose the collection. Once you reinstall all you need to do is point the software to the folder where the files are and the software will recreate the collection. (So yes, try a reinstall.)