For stacking movies use:-
cd1
cd 1
cd.1
cd_1
cd-1
You can replace cd with :-
"dvd", "part", "disk", and "pt"
I don't like using movie 1 and movie 2, since it would stack movies that are sequels rather than multipart.
At the moment tv shows have to be added individually, I will probably end up changing this, it's not a high priority though.