So after doing some research I've brought my DVD list to this:

Turbo Jam
Tae Bo Amped
WATP
Winsor Pilates

Would you guys agree this would be a "solid set"?

If you have cable tv, check your ON DEMAND channels for Exercise TV. You can try out full versions of Turbo Jam and WATP for free there.

Tae Bo amped is pretty intense. If that's the level you're at, you might find WATP to be too easy.

I've only done Turbo Jam and WATP...

TB drives me nuts... can't stand it. I LOVE Turbo Jam and WATP is okay but I only do it to get the job done so to speak.

Those are good selections in general but if you want to build a good muscle base I'd add something "Weight training like" to that mix you have mostly cardio there. Pilates will help with core strength somewhat though.

Might want to check out "Get Ripped" by Jari Love - Good place to start it's more aerobic (high-rep sets) but it will get you a good beginner muscle base despite what people say about high-reps.