Well, why not try Audacity.
Its free, and is a great simple sound editor, allowing you to do simple things like taking out noise from tape/record decks like hiss and pops, and changing quite a few complex settings, and since its open source, people can create new plugins for it etc to allow it to do more stuff.
There are more complex programs available, but they cost money.
Heres the link to it:
Give it a chance, and I'm sure you will like it
It also allows you to export as Wave/MP3 and OGG I think, in different quality settings, and also allows you to select the recording/line in source very simply.
I hope this helps.
Note: Just simpyly place the tape deck in Line In, and select this on the program, making sure in sound properties on the task bar it isn't on mute and at a suitable level (about half way, maybe a little bit more)