I just bought a 2000 impreza outback sport. A guy has a good deal on the complete interior from an 00 outback limited. Will any of it it fit in my car? Thanks.

They are quite different. The seats will fit, but they will sit up higher.

Ok, the seats are the main thing I want, although it would be nice to replace the carpet. Mine is very dirty and completely full of dog hair from the previous owner. The seats being higher isn't a big deal at all, but are they bigger? will there be less room? Good idea or bad? thanks.

Yeah the carpet won't fit either. The seats won't be much bigger physically, just sit up higher. If you're very tall, it's probably not a good idea, but worst case scenario is, you can just change it back out.

You might get away with the front seats. The rears, I believe, will NOT fit.

I swapped some front buckets from a Forester into my Impreza last year and all I had to do was swap the mounting rails from my old Impreza seats onto the bottom of the Forester seats. The mounting rails from the Foz were much higher than the Pretzel units.
Just like everything else I do... I discussed this swap in a youtube video:

^Yes, I should have clarified, the front seats are bolt in. And the rail swap will help in the height difference.

Alright thanks guys. I can get it for $100, but maybe its not the best idea if I'm only gonna be able to use the front seats. = (