Burn incremental backups to cd / dvd

I'm using True Image 7.0 with the latest update (63. I have using the incremental backup feature and now have about 18 files spanning the period 31 May 04 through 14 November 04. I have always burned the images to cd. I now have a dvd burner and would like to continue to burn backups to external media but am confused about the process. Shall I continue to burn every file to disk? At some point does it become worth it to re-image (as opposed to continuing to use the incremental) the drive just to get back to a manageable number of files to burn to cd?

Thanks

Vince