They may or may not grow and they may or may not be roses. On an other forum someone bought some and they turned out to be radishes.
On your original question, with real rose seeds, except for a very few species roses, the results can be any form or color from the seed's parentage. Just like with humans or any other living thing the babies are a combination of all the genetic materials from the entire family tree of the baby. It's a matter of which of the traits become dominant in the mix and present themselves. A purple rose seed could produce yellow or red blooms if there are some of those colors in its lineage. I will tell you that from my breeding experiences the default color and form of most roses is a 5 petaled pink bloom. I've had dozens of them to prove it!
