Its because your output is uncompressed AVI. In order to place on a DVD your output file will have to be DVD Compliant MPEG. Encode at 8000Kbps and you will find that the file size (for your 33 minute movie) will be around 2.2Gb


Good luck

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IBM A51p with 160Gb Boot Disk, 160Gb external Firewire Disk, 2Gb Memory and a super duper sound card, 17\" TFT Monitor etc etc etc
Sony TRV33e : Sony TRV310e : Canon XM2
ULead products mostly including Mediastudio Pro (V8.0), Video Studio 8, Movie Factory 2.0, Premiere Elements

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