Files on VCD must have certain format: resolution etc. If you have the
application that can create vcd, the easiest way to find out is to try to
create it - if the file does not conform, the application will tell you what
would be accepted.
Yes, the freeware version of TMPGenc will convert a wmv (must change
..wmv extension to .asf first) or avi file to a VCD compliant mpeg1
file for burning to CD.