files not showing up after burning to disk
 

I have some french movies I tried burning to a DVD+R disk recently and though there appeared to be no problems at all during the burning process, only one or two of the 6 files show up when I look at the disk. The rest are just absent. Anyone familiar with this phenomenon? I've burned others with no problems at all. I just don't get this. :(

Windows XP SP2
burned it with roxio easy cd creator 6 as a data cd.