Welcome. I am still new here also but...
1. Karma is given out to who you see fit based on the content oh their posts. There is good Karma and bad karma, and you can give and receive both. Too much negative karma and you can get banned.
2. A flame is a rude comment made to another member. Basically Internet name calling for the most part. Not to say you can't disagree with someone. Just don't say "You are an f'n idiot." Debate constructively and intelligently and you'll be fine.
Also, make sure you read ALL of the rules due to some of the sensitive subject matter that tends to be disscussed. Common sense prevails here...