Before we get into this I want to say that this is obviously not a preferred way of doing things. That said, if matters at all to you that you will get into trouble for it then you probably won’t be able to go through with it.

Be aware of the consequences
The legal stuff, the fact that you have basically ruined your reputation (even if the guy was a notorious dick), those are all, obviously, inevitable. The less obvious part is inside your head. You spent your whole adult life up until that point eating shit and then you exploded, you can't ever know if you would or would not do that again. It was a loss of control. It is easy, at this point, to have your whole life spin out of control, have all your addictions and potential addictions get the best of you. You don't feel as if anything is in your power anymore. On top of all that it feels like it's your fault, even if the bastard had it coming for years before that.

You will be blamed. No matter how bad it was for you punching your boss, throwing him/her out a window or down a flight of stairs, will not make you sympathetic. If you bitch about how bad it is to your family and friends you might be able to milk a little false sympathy, but tackling the problem in the most straight-forward way is frowned upon. People will use the situation to feel better about themselves, all the times they took shit and did nothing about it will make them feel like they are more disciplined and sensible than you.

Note, also, that if you win the fight with your boss he, if he is a guy (and often even if it's a woman, but not always) will have to destroy your life in order to soothe his/her ego. For a man who sees his position at a place of work as an emblem of everything he has achieved with his life, being physically humiliated by an underling is not a small thing. He will not rest until you understand, once and for all, that you are the lesser.

If you do do it... (Note that this is not suggestion)
You may want to make it count. Do not stop halfway though it hoping that an apology will make things better. If you say something bad you might as well keep going with it, say something else. if you throw a punch, throw a bunch more, and some kicks. Make them feel the full extent of your wrath. It's not as if it will alter your position much. You will likely wind up in jail even if you don't. If you are going to get the death sentence for one thing, you might as well get it for four or five.

Conventional reasoning:
Do a good job. Work hard, be conscientious with your tasks, and friendly to your co-workers. Your boss will see that you do a good job, that you are a team-player, and are too valuable to lose to office politics.

The reality:
Your boss does not care who does a good job as long as the job gets done. The fact that you do a good job does not single you out as the boss is more likely to think that his or her management skill is what motivated you to do a good job, and that a trained monkey could do your job if they had an awesome boss too.

Conventional reasoning:
If you have a legitimate complaint about a co-worker you should document it and report it to a higher up.

The reality:
This hinges on whether you are a better suck-up than the person you are reporting. If they are the number one lackey you are screwed no matter how legitimate your complaints are. You will be discouraged from taking any actions, your name will probably be mentioned to the subject of the complaint and your life will be made hell both by your boss and by the co-worker.

Conventional reasoning:
Try to reason with the problem co-worker and come to an amicable working-relationship.

The reality:
Unless this reasoning takes place in the back of a windowless van and they are duct-taped to metal chair to which you have attached live jumper cables it probably won't come to anything. In fact, what it might do is indicate to them that they are having an effect on you, thus making them feel powerful.

Conventional reasoning:
Confront the co-worker, meet fire with fire. If they are making your life miserable you should go to them and tell them that you are not intimidated, and that you know what they are doing. Get in their face and make them understand that you are not just going to passively sit down and take their attempts to undermine you.

The reality:
Any show of aggression will be met with the trademark puzzlement of the passive-aggressive. They will do their best to avoid confrontation and to pacify you, but then ratchet up their plans for your destruction.