Just tried to burn a 2GB folder to a DVD and same error report - in full it is:
"The drive reported an error:
Sense Key = MEDIUM ERROR
Sense Code = 0x72, 0x02
SESSION FIXATION ERROR WRITING LEAD-OUT"
Thanks ever so much for your answer - that was my worry too. Its just massively annoying since I have hardly used the drive at all ;-(
It did burn a disc of about 900MB with no problems - not ure if that signifies anything?