I tried to burn a DVD recently on my mac and encountered an error during writing, right at the start (while writing the lead-in). At first, I thought my drive’s dead, since before that, even reading regular CDs was very slow. I googled a little and came across all sorts of explanations, from “you have to reinstall OSX” to “reset PROM”. Knowing that these can’t be possibly the cause for the write error, I went to buy myself a laser-lens cleaning disc. Inserted it, played the “cleaning track” twice and tried to burn the DVD again. And look at this: Works like a charm again! So, the problem was actually dust on the lens, I guess. And that’s also explainable: The macbook’s drive is a slot-in drive, which means, there’s always a little slot open in the notebook’s case where air is able to stream in. Since the macbook pro has a tendency to get hot pretty fast when running processor intensive tasks, the case fans transport a lot of air out of the cooling slots at the back of the machine. Now, the air has to get in somwhere – and with air, there comes dust. Voila.
No need to reinstall your osx.. Actually, you might only make the problem worse because you might encounter DVD *read* errors while installing, and that would be.. pure irony. :-)