dTunes help

With dTunes, i could download .mp4 files from megaupload.com using my iphone. Now when i'm doing it, I click regular download and it just stays there on the same page. Does anyone else have this problem?

Also how do i put videos onto my iphone? I've dragged the file onto my movies folder on itunes, synced it but it doesn't come up under video. Also the movie file is an .mp4 format

Thanks