Dont know about the cassete to cd, but would you really want to try and put analog music into a difital format? I dont think it would sound very good.
More than likely you can download most of the songs you have on cassete from the internet.
www.kazaa.com has the kazaa program available for dowload that lets you dowload music from other people's computers. However, this program is considered as spyware so if you dont want spyware on your system, dont download it.
Personally, the only problem i have with kazaa is the pop-ups it causes. minor annoyance but annoying none the less.
-CP
BTW--thought i should add that though i use kazaa i make sure to shut it down completely (using the system tray) when im not using it. At least that way its not calling home ALL the time.
-CP