Keep it in DivX format and buy this player:
Philips DivX player
I got it for $63 shipped. It has played every DivX ( version 3-5) and XVid that I've thrown at it. You can even put 4 DivX movies on a DVD and it will play all three. In your case, you could put that large DivX on a DVD.
To put it back into DVD format (MPEG 2) you need TMPG Encoder. If cutting the credit will get the movie down to size to burn on a CD, then use VirtualDub to edit it, and make it shorter. You can also use VirtualDub to re-encode the movie at a lower bitrate. I believe that Nero can covert a AVI movie to DVD format as well, if you have the ultimate Edition.
Edit: To your original question: TMPG Enncoder will easily convert a DivX to VCD format. You can turn on the expert features to lower the bitrate and sound bit-rate to fit on a single CD. You can also set the end frame to chop out the credits. I've done this many times. In many cases, you haev to use VirtualDub to extract the Audio to a Wav file. Then Have TMPG Encoder convert the video from the AVI and the sound from the wave file, into a VCD format. Then use VCDEasy to burn to CD (or to make an imaeg file which Nero can burn).