Probably one of the best things to do for someone posting a question, would be having a message at the top on the question box that says “we’re trying to help you, but you might not like some of the answers we give, so please bear with us.” or “internet forums are like the highway system: Most of us know what we’re doing, you may not like what happens, but we all try to share the road with everyone.”
As far as being nice goes, this is one of the friendliest forums I’ve been to. I’m on one that has a for sale/want to buy section and I’ve seen a couple people get screwed over by the seller, and several members will do a little digging and find the seller’s name, facebook page, phone number, and even their home address and post them to the forums; they even took a picture of the guy’s house and sent it to him to show that they meant business in making things right.