I finished encoding my movie and the overall size was 773MB. Everyone said a vcd holds 800mb. Why can't i burn my movie then? Nero keeps ejectingthe disc saying there is not enough space

If you're authoring with Nero, make sure that you are setting
it to use mode 2. This will right the information directly to the disc, skipping over creating the usual filesystem.

Or make it easy on yourself, and author it with vcdeasy.
you can make chapters, menus, etc... AND you can
use the program to burn the movie, or just create
image files for Nero (I always burn with nero actually)

good luck

-Jeff