Oh ic what you mean...
myeah, I've never been a big fan of that. When you leave a cd or DVD open that's basicly asking for problems. There's loads of stuff that can go wrong, and then your data is left useless.
I usually take regular cds for smaller amount of data, and if it's gotta go on 1 DVD, I save it up in a seperate folder until it's full enough to fill an entire DVD.