I keep all mine on beech shelving.
1. shelf for SCiFi
2. shelf for Westerns
3. shelf for War
4. shelf for music etc etc etc etc
At the moment they are all mixed up




Similarly shelved by genre.
Top shelf - split 50/50 Vampire/Zombie
Second shelf - Other horror/18 rated action.
Third shelf - Hong Kong action
Fourth shelf - Comedy/TV shows/Other action
Fifth shelf - Animation and everything else.
Don't ask me why I keep the 18 rated stuff out of the reach of children, when I have none
Guess it's just so that I don't have to bend down when I need my "gore fix"