how to use videos and still load faster..

Okies my lovely super powerful mutant developer extraordinare amigos and amigas.

riddle me this... working on this site.. http://f5fostercare.co.uk/
Wanted to use video backgrounds on the top slider and created and added two slides with videos which were hosted on my slider. But that made the page go over 7MB and after a while kept on crashing. Now i have changed one of them to a image bg and seems its loading fine now..

So my question to you is - Is there a way to minify the videos ? they are all just over 3MB each. Me and the client both loves the video idea but needs to sort out a way to display and load the site properly.. if not will fall back to boring images..