Man Iím sorry that I canít help you with the Ubuntu 8.04
But Iím sure that I can help you in another way.
Go to the site http://freecddvdburner.com/
And download the program StarBurn, this one is a powerful burning a grabbing software with not only you will be able burn CDs also DVDs, Blu-Ray and HD-DVD media.
It also allows you to split DVD-Video discs into smaller parts and burn them to DVD writable discs and watch DVD videos directly on your PC.
And the best of all is that is a 100% free.
Hope you funded useful.