iDVD Dual-Layer Burning Problem?

So I encoded a 3.5-hour video within iDVD and burned to a dual layer DVD disc.... twice. Both times, any DVD player I put the disc in (even my own MacBook Pro that I burned it on) refuses to play any video on the second layer. It just freezes when it reaches the layer change.

Seeing as these types of discs are so dang expensive, I wondered if anyone else had this problem and knew of a fix; before I go out and try a different brand of dual-layer media.

I have not tried to burn a movie on dual layer disk yet, due to cost as you suggested. But I have had problems with dual layer disk in my older DVD player. Some times if I press the enter button the second layer starts to play, but not all of the time.