A list of different sort of things, an overview of genres:
The Red Shoes
Muriel's Wedding
Spartacus
Britcom (pick one):
Fawlty Towers
Black Adder (I recommend the Elizabethan one and the Restoration one)
AbFab (The series is broken into the last season in one and the earlier seasons in a set or three individual DVD's; the earlier stuff is funnier)
Monty Python a low number or the whole bloody business
Music (pick one):
Woodstock
The Last Waltz
Stop Making Sense
The Rolling Stones: Bridges to Babylon
Down from the Mountain
Walt Disney Treasures: Mickey Mouse in Living Color
Casablanca or The Big Sleep
Training Day
Crouching Tiger, Hidden Dragon (Superbit)
Modern Science Fiction (pick one):
Starship Troopers
Dark City
AI
All are good films and are known to have good transfers as far as sound and picture (okay, the Britcoms may not be top of the heap, but their content is strong enough to overcome any shortcomings).