Sorry you are regretting your decision based on a few people's actions. If you don't like someone, just check out a different server, trust me, there are plenty, and they aren't all run by the fun police. Wear a ban from a server you hate like a badge.
If you are going though, please spare us having to read your complaints and just go. Give your ID to your friend or something for their birthday, and use the money you saved off of buying them a gift to get Gmod.
But trust me, if you think this community is bad, you don't have a clue what Facepunch is like. If you think the grammar police are out to get you here, wait until you see the Facepunch forums. All your posts are run through a spell checker, and if you make too many errors, you can be banned. And the people there are just as harsh when it comes to correcting grammar, except instead of correcting your posts and showing you what you did wrong, they'll just give you an awful spelling rating. Which doesn't really mean anything and isn't worth anything, but people pretend it does.
Then again, there are so many servers, you'll probably be bound to find one that you like, and where the people like you.