Hi Colton,
I actually don't use iTunes myself (never liked it) but you shouldn't have to download it again onto your laptop as all you are doing really is transferring the MP3 music files from a folder on your PC to a folder on your laptop.
There's lots of ways of doing this. You could burn them onto a CD or DVD (in data format, not audio)... you'll get well over a hundered on a CD, many times more in a DVD.
Otherwise you could use a memory stick thing. A 1GB one will hold about 200 or so, maybe more.
Otherwise you could investin an external hard drive and stick them all on that and then you could take them wherever! If I were you I'd do this. Externals are after getting well cheap these days and they have the advantage of laeving your internal PC HD space free. You just plug them into the USB port on your computer and off you go... just drag the files in and they'll copy automatically.
www.komplett.ie have decents ones for cheap.
Hope this helps you!