I use Abyss Web Server(
http://www.aprelium.com/abyssws/), its very simple, and easy to set up, and best of all, its FREE. I've been using it for pics, movies, and my personal site, along with hosting files for other people and I've never ran into any problems. The only thing I've ran into is, when people are downloading larger files(20MB+), my connection does seem to slow down, I'm using verizon DSL(which has to be the slowest DSL connection around here), but they haven't said anything about my transfers or bandwidth, so I'm running with it until I'm told otherwise, or they just block the port.