you can use winrar and compress it between 2 files.
here are some settings your gonna want to use:
set compression method to store ( this is because avi dosent compress very much anyways, and with store, there is less chance for it to screw up)
and check off "Put Recovery Method"
then just set the volume size to 500,000,000
and it will make 2 files for ya to burn.
later
JB