I think the concept of resurrecting dinosaurs and other prehistoric creatures using preserved DNA is plausible. However, it would take generations in order to breed a "pure blood" dinosaur, because there would have to be a surrogate mother (unless better technology comes out that circumvents that). But obviously, the point of the films is the "what if" and the consequences. Again, danger of knowledge is present. Just because we have the power to bring back the dinosaurs, is it worth it? The films seemed to express a yes and no (although admittedly, it's been a while since I've seen the films, so I could be wrong). The weatlh of knowledge acquired from these prehistoric creatures, their lifestyles, and the methods to bring them back is a huge step in technological and biological advancement. But you better have huge fortified and electricified fences... or else, the Tyannosaurus and othe carnivores will just break out and enjoy an all-you-can-eat buffet. I think the films also demonstrated that business and money (ie using the dinosaurs as attractions in the titular theme park, Jurassic Park) drove the characters and the theme park itself to tragedy and in some cases, extinction (excuse the pun). With great power comes great responsiblity, and if money comes into play, it could and usually will become a disaster...
OR, we could go searching for prehistoric creatures rumored to be alive today!
