Would the Name Dinosaur Need to Change?

Well, it is a good question, but it wouldn't make sense to change it my honest opinion.

Also, there some dinosaurs that weren't birds, for example, Spinosauurs, was more closely related to a crocodile.

dinopetrex

terrible birds.

The Dinosaurs were an offshoot of the theraspids, an ancient group of quadrupedal reptiles. They gained an evolutionary edge by adopting a bipedal stance, towering over their relatives. So, that in itself tells us that they were reptiles at one point in time, even if it was the beginning of their evolution. The Dinosaurs were an exceptionally successful group of reptiles that were indeed so successful, began to break into different groups. Theropods, ornithopods, sauropods, ceratopsians, you name it. They also adopted feather like quills, whether this was for display or temperature regulation isn't 100% certain. The smaller theropods, especially in the Jurassic, began to take certain forms. Archeopteryx is one prime example of this.

So, in short no, the name shouldn't change, As they were "Terrible lizards" for a long while.

I dont think it would need to change. Dinosaur is a symbolic word, but it is after all a word, a word almost everyone knows. It shouldn't change, because it will take a long time to get used to. dinosaur was created in 1842, it has been around for 172 years or so. Its going to be long before people stop saying dinosaur. Plus dinosaur is a cool name. :)

I would be against changing the name. After all, the name is in the public mainstream already and is what people associate with the animals. Changing it would create confusion and be detrimental to public interest in dinosaurs I believe.

Also if we change "terrible lizards" wouldn't we also have to change "tyrant lizard king" , "spine lizard", and "other lizard" . Too much name changes, with too many genera of dinosaur

No, evrey single dinosaur that had "saurus" in its name would need to be changed to "petrex" so Tyrannopetrex or Giganotopetrex. and it would just confuse the general public.

No. It would be overly complicated and confuse the feeble-minded. 12.5/10 would not change.

Not a chance. That'd be confusing. 

It won't happen. I heard of a scientific rule preventing the change of a genus/species same. I guess dinosaurs would fit into there.

Oh yeah, the point Sc-Fi King is true, things like that exist to help prevent any confusion.