What's the best program to create an installer?

I'm looking for a program that will install several different files to different folders on another computer. I'm transferring some files from one of my computers to the rest of them, and I believe it would be slower, but more fun if I did it with an installer app. I know without it that it'd be faster, but I may need an installer in the future. What's the best freeware program, and the most powerful non-freeware (most options)?