Using Sharepod to delete songs but the titles are still on ipod. :(

Hello everyone, long time reader first time poster. 🙂 I bought my sisters 80 gig classic and am trying to delete some of the song son her ipod. I have a pc with xp on it, and everything seems to be going ok. I deleted a ton of songs using sharepod off of the ipod, but when I went to use it today they were still there but I was unable to listen to them. So it deleted the song but not the title???

Also, when I want to sync it says it will delete the songs on the ipod and replace them with my itunes library. Those are all my cds and I want all of the ongs not one or the other so what do I do to add too the ipod without deleting the songs already on there.

Thanks in advance and have a great day!