i aspire to be a great internet filmmaker ,such as smosh, and i have everything i need. I have tapes, a camcorder and a tripod. the only thing left i still need is i need to know how i can get music to fit the mood of a scene and still avoid copyright issues. where can i do this?

get garageband/imovie

www.incompetech.com

this guy has everything for free... or you can get buyout music, which is usually about $30 a track... or more for more popular stuff obv.

my computer is a windows. will that allow me to have garageband?

That's what I use, it is pretty good.

is garageband free? i have windows so will it work on it?

No, it is built into the Mac, but there are a ton