Something doesn't sound right. You're still not finished the game, and you're just posting your comments about it right now, so I'm guessing that you just installed the game. You have
to install Steam and connect at least once to register the game. When you did this it would have downloaded the updates. If you installed the game recently, which it appears you have, then there is no way that you could not have the updated version.
Luckily steam can be uninstalled or kept from running.
No it can't. As far as I know, Steam always has to run with every Steam game. You can set it to run in an offline mode, but it still has to be installed and it still has to run.
Do you even you a legit copy of the game? If you don't then nothing you have said is worth anything because you aren't even a paying customer.