Well, mpeg is the format used for VCD, so they may already be ready. Some burning software, like Easy cd Creator, will convert them for you as they make the disk. Or you could use TMPenc, which is free, to encode them. Best thing is to go here:http://www.dvdrhelp.com/
where
you can find articles on all the things connected with making DVDs VCDs SVCDs etc. Plus info and links to all the software you will need.