the video i want to play is 640 x 480. Is there any way to make the video smaller? Because when I play it, the video is too big for the music player.

Do I need to download a program?

The EMBED tag allows the attributes "height" and "width" to constrain dimensions, so you could try this:

But, of course, it won't actually make the file size of your video smaller, and the proportions will still be the same if the movie is downloaded and opened.