I have a variety of tapes and DVD's, and pop a different one in each day to avoid getting bored. I have plain old floor aerobics, step, strength training, circuit, yoga, and even a belly dancing video!
Some of my favorites are tapes I originally got in the 90's, including a Jane Fonda Step-Aerobics tape that came with a bench, and one with Elle McPherson called "Your Personal Best."
I also have lots of Kathy Smith DVD's, because I like her stuff.
If you go to Collagevideo.com you will be able to browse hundreds (if not thousands) of exercise DVD's. It's easy to find the type you are looking for, and they have snippets of the work-outs you can preview. I've gotten almost all my exercise tapes/DVD's from there. They have a great return policy, too, if you get the DVD and decide you don't like it.