Donald, I claim no expertise in these plants, but I think you're on the right track with your guess of Coryline 'Red Star' for your "trunked" plant. There are other varieties of red Cordyline, too, so it may difficult to figure out the exact cultivar for sure. I think these used to be sold, incorrectly, as "Red Dracaena spike plants."
Sandi, again, I claim no expertise in these plants.... Although most Corylines have a trunk there are some clumping, short-stemmed varieties, like Cordyline Festival Grass™ 'Jurred', that make it really confusing. From what I can gather, the way to tell them apart (when not in bloom) is the leaf arrangement. You'll need to look at the leaf bases and see if the leaves are arranged in a rosette style (like a Yucca) or in a fan-style (like an Iris.) Coryline would be rosette-style while Phormium would be fan-style. I can't really tell from the photo which arrangement you've got going on. If it blooms, then it should be easy to tell the difference.
I really like your pretty pot and hope it does well in the garden show.
