Can't Put Videos In iTunes. What Am I Doing Wrong?

[Rmbxr9]

I used to be able to do this, now it's just not working.
I'm looking to take a video, convert it to an MP4, and drag it into the "Movies" section.

I've tried 2-3 video converters: Videora, Any Video Converter, etc.
They're MP4s, but when I drag them into the "Movies" or "TV Shows" nothing goes there, nothing happens at all.

I'm using an iPhone 3Gs, running the iOS5, and using iTunes 10.5.2.11

What am I missing here? Is MP4 not the right format? I thought it was
Thanks

 

[Rmbxr9]

Anyone?