Unlike music files, which are predominantly in the popular MP3 format, video files have many many formats, such as AVI, MPG, MP4, MOV, WMV, and the list goes on. Stubbornly, Apple's products will only play movies in a certain encoding of MP4, and hence most of the movies you will typically download on your computer (AVI, MPG) will not work! So, how do we overcome this problem?
A whole programming industry of video converters has emerged over the years to help alleviate this problem. Unfortunately, most of them charge you for it, but if you snoop around enough, you'll be able to find some sweet freeware which will do the job for you.
What I've found today is a program called "Videora"
Now I haven't tested this software on Windows but it looks to be pretty decent. This program has a step by step guide to converting your videos for the everyday user. Check out the tutorial HERE
Just in case you missed the download for it, here it is.
Being a mac user myself, I use handbrake to do this for me, a very powerful video encoding program (and free!), despite Videora offering a Mac version. So let me know if you've had success with this program!