I'm planning on making a skate video this summer and I'm looking for a program that will let me add music, combine separate video files( like scenes in a movie ), and add subtitles or like add a frame of Skaters name/cool background/ and music and any other cool stuff
If you're running Windows, Windows Movie Maker is already included. Just go to Start>All Programs and look for it. It should be there.

If you want to look into a future of Video Editing, I've been using Sony Vegas 6 for a while now, and it's really impressive.

EDIT: If you can't find it on the Start Menu, open My Computer, click on the C:\ Drive, open the "Programs and Accessories" folder, and find the folder that says "Movie Maker". It should be an EXE in that folder.
yeah for basic stuff use windows movie maker/imovie whichever ur computer has if ur willing to spend a bit of money go for Sony Vegas 7 imo its pretty good for making videos quickly slight learning curve but if u play around with it ull be fine
Dick+strings= owww
Another option is Adobe Premiere, or if you're a mac user, Final Cut Express (unless you're willing to fork out for the high-end version, Final Cut Pro).

I remember using Premiere 5 or 6 a couple of years ago and it seemed to do the job, and I'm using FCP in my uni course now and it's the shiz for video. Audio, not so good, so I advise you do all your EQ/effects in a dedicated audio program (although if possible I'd highly recommend that for any program) and then arrange it in whichever program you wish to use.

In saying that, Windows Movie Maker for Windows and iMovie for mac provide an excellent starting point for budding film-makers.