One where the science is at least vaguely possible is Jurassic Park. You would have to get hold of the book which goes into a lot more detail about the restoration of dinosaur DNA.

An old one with good science in it: The Andromeda Strain, about an alien virus.

Another oldie: The Fantastic Voyage, about a group of scientists who are shrunk down to tiny size and injected into someone’s body.

Alien. The alien was based on some species of wasp like the tarantula hawk moth which paralyse a creature and lay their eggs inside it. The developing larva eats the creature alive from the inside.