You cant make VCD's out of Divx Movies. VCD's use mpg1 for their video format, i guess nero will try to convert it for you, but i would rather see it working myself before i waste a cd.
It can be done, its not fun.
Use TMPGEnc to convert it to mpg, it will take a LONG time. My guess is that then the file will be WAY to big, since Divx is way better compression then mpg, but you should be able to split it (get a program) and then burn it to cd's.
To tell you the truth your better off just buring all your divx to CD's (data) and getting a video card with video out to watch them on the tube.