Any question answered...

I want to get more exercise and have the opportunity to work on form...Would anyone suggest buying a different trainer?

Yes, for general aerobic training plus improved form, get rollers.
http://www.wiggle.co.uk/tacx-antares-professional-training-rollers/

And, to confirm: this is the kind that I attach the forks to and my back wheel is on a thing-a-majig, right?

No, your front wheel sits on the ground and the turbo attaches to your bike at the rear axle; that might be what you meant, of course.