This question, and others like it, reflect the important and significant disagreements between proponents of evolution and those opposed. However, it is instructive to understand where both sides are coming from and why, ultimately, evolution must be rejected.
Evolutionists adhere strongly to the philosophy that natural selection and other factors will allow the most suited organisms to survive in their environments long enough to pass on their genetic material to the subsequent generation. Often cited are the Galapagos finches who represent an impressive range of characteristics, each suited to its particular environment.
The first point to be made however, is that there is an assumption that everyone who disagrees with evolution is automatically a certain type of creationist. There certainly are creationists out there who believe that the earth is 6000 years old and so naturally will reject any notion of evolution taking place given the age of our world. However, other creationists, proponents of Intelligent Design theories and others, easily reject evolution on the basis of a number of important factors.
Despite vehement and often astonishingly closed-minded promotion of evolution, there are a number of factors that call into question these notions. They include:
a. the absence of transitional forms in the fossil record – the fossil record clearly shows only fully formed organisms, not in-between forms that would suggest that evolution was taking place. The Galapagos finches are simply different variations that could very well have all appeared at the same time
b. the presence of fully formed, highly complex structures like cilia, on otherwise primitive organisms like single celled paramecia
c. the unanswerable conundrum of where the first point from which the Big Bang took place, actually came from
d. the concept of irreducible complexity – the human ear is made up of 4 bones, each of which is required in order for us to hear. If one of the bones was taken away, our sense of hearing would disappear which would make the humans whose ear bones were still evolving, deaf – and subsequently lunch, for large predators. Hardly the best way to continue the development of the species
In terms of the dinosaurs to birds question, one need only examine the breathing systems of these to types of animals to debunk this concept.
Many reptiles are able to breathe through their skins. Birds, however, have positive pressure lung breathing systems which are required in order to ensure efficient oxygen transfer to the blood to power flight.
It is a large leap to make that birds evolved from the dinosaurs, when more basic questions like the origin of the matter in the universe cannot be answered.