help needed

I recently brought the s30 and love it... only problem I'm having is putting videos on it. I have converted videos and finally was able to play them on my phone except the video screen size was small as hell. Does any1 know how to make them play in full screen. I finally found those "trick" videos and would love to start using them... or even convert some movie clips for my own entertainment but having them not taking up the whole screen sucks... any help would be great. thanks in advance