I always try to run a table in a way that I would enjoy playing. I am a deep role-player. To me it's about immersion and living and seeing for a while through the character's eyes. Things like silliness, side chatter, and so on are detrimental to immersion and so are strongly controlled at my tables.
Teamwork and cooperation are also important to me. To me, roleplay games are pure positive sum games and non-competitive. Played right, everybody wins. Players should be working together to solve the problems they are faced with. I also expect the players to be cooperative with me. I try not to lead characters by the nose, but I do expect characters to be focused on the game and pick it up when I gently nudge them.
With that said here are the rules I have found necessary to preserve this sort of table.
Real dice rolls A die has to roll to count. Dropping it on the table does not count and I will make you do it over. You roll dice when I ask you to. Any other rolls do not count. Once a die is rolled it must remain untouched until I have acknowledged the number. If the die is touched, then I get to arbitrarily pick a number for that roll. If you seem prone to problems here, I will make you use my dice tower.
Rules challenges I am not perfect and I make mistakes. If you think a ruling during game up was in error, find the rule or rules you are basing that challenge on in the rulebooks and get my attention. We will go briefly game down while I look at the rule in question and make a call. That call stands until the end of the session. After the session ends, I am happy to discuss it in detail, and to correct results of a mistake even to the point of retconning a game up event.
I run an open table I celebrate diversity and welcome all sorts of people to my table. As long as they don't make each other uncomfortable I want them all in my game If another player's actions at the table trigger you, talk to me about it. I will try to find a balance point that everyone can be comfortable with. If I can't find that then either or both the players will be disinvited
In general I find that, with a good table, these rules seldom come up. But i have found them necessary with “pick-up groups” and an occasional disruptive player.