I'm kind of like that aswell Vipco. I've never gotten round to backing up any of my films as of yet but I've got some old videos I really should back up onto dvd, they aren't gonna last forever. But as for getting multiple copies of films, yeah, i'm really bad for that. If I see a copy of a film I already own and it's got a different cover that I like then I'll usually buy it, It's kind of a waste of money really especially when I could be buying stuff I don't already own but I just can't help it sometimes.
I think i've got something like 6 different versions of the First 'Evil Dead' and four or five of 'Halloween' and 'Zombie Flesh Eaters', their the most extreme examples