If you lose control of yourself or lose awareness of your surroundings when buzzed/drunk, I agree. Stay with the virgin drinks. Just realize that people can be quite territorial, boisterous and aggressive in pubs. They can act before they think. Which means that you should NOT act before you think.
Be friendly and approachable, don't pester people who don't want to chat with you, don't intrude in groups/conversations, don't sit in a seat if someone's stuff or drink is there, don't talk to girls if they're with their boyfriend, etc (unless they BOTH involve you in a conversation). *Definitely* do NOT stare at people, and when you're working your way through a crowd to the restroom, DON'T push, yell or say "Move." Be polite and say "Excuse me" just loudly enough to be heard over the noise. And don't look angry, look neutral/pleasant, or you'll be asking for trouble.
If you get any bad vibes, or people start getting aggressive with you, leave.