just because it's CGI doesn't mean it's "pixar", as pixar is an animation production company and not a type, though lots of people such as yourself will lump them all together.
big 3 CGI companies: pixar, dreamworks, blue sky
pixar (disney) - toy story, bug's life, finding nemo, etc.
dreamworks (paramount) - shrek series, antz, shark's tale, etc.
blue sky (fox) - ice age series, robots, etc.