Video converter

Is there a module that will let a user upload a video, and that it converts the video to example mp4 on any format that wont make my server lag when playing back...

Thanks

the default video module - when using the .h264 will convert your videos to both webm and m4v. If you have the html5 video module installed, then the video player itself will be using html5 (from your browser - provided your browser has an html5 player) with a flash fallback (for non html5 browsers). Your lag may not be because of the videos themselves, but any number of other possibilities. ie your computer, your internet connection, your isp, your web server, etc.

I will contact my ISP...thank you for you're help ;))