making LETTERS in microsoft paint

I'm trying to make something, and im trying some new animation things. The Problem is, to do it i need to create letters in paint. How do i do this? or is there another program that will save in BMP/JPEG format that will allow you to make letters? and have all the stuff it paint? i intend to put all the pictures together using windows movie maker, so it needs to be the right format.

any ideas anybody please?