How to Play Video Files on Samsung Gravity?

How to play video files on Samsung Gravity?
I am trying to play music videos on my Samsung Gravity but it doesn't give me the option to play the file and every time I transfer a video over it puts it in the "Other Files" folder. i already transfer for it to a 3gp...but it's not working right it don't show no play button. I loaded the files to my memory chip and transfer to the phone. but it don't work can someone help me please. if so can you put it in simple words or a video on how to do this.

 

err.. this should be in the general help section..

 

ooo iight na well i saw cell phone stuff so i just fig. it goes here...