It sounds like you have a lot to handle with three small children (are the two and a half year olds twins?)--I have only one, and I think it's a lot! Children will do just about anything to get our attention. He probably senses that you are busy with everything else, and he knows that acting out will get your attention, even if it's negative. In terms of the swearing, I'm told the best thing to do is to NOT make a big deal of it. As awful as soap and hot sauce are, they are still getting him attention of some kind..... I've also been told to talk to the child in private, when things have settled down, that those words are ugly words, and we try not to use them--sometimes people do, but we try very hard not to because they are just not pretty or nice (whatever terms he can understand). And if he continues to use them, just say, "remember, that is not nice. we don't use those words", and keep it simple--removing your attention from him and the behavior.
And then if you can find as many good things as possible to praise him about--and really focus on the good things that he does. He really just wants your love and attention, and will do whatever he can to get it. Sometimes when my almost two year old is acting out, I give MYSELF a "timeout" and step away from the situation (without leaving him entirely alone of course). I actually saw that on that Nanny show! And I tell him that I will be ready to play with him when he settles down, and I settle down. Children don't fully understand the meaning of time out until they're three, and it could just seem like a game to him--but withdrawing your attention from him might send the message. Plus sometimes I just need to step away so that I don't get too mad. I have to remember that he is still learning how to be a good person, and it's my job to model what that is. If I get too angry and yell, then it's going to be silly if I tell him not to get angry and yell! Plus, they really are just looking for our love, so if I can calm down, then I'm much better able to talk to him and give him that love.
I'm reading a great book called "Positive Discipline" that I got at the World Eye Bookshop, (they also might have it at the library). It's written by Jane Nelsen, Cherly Erwin, and Roslyn Ann Duffy, and it's packed full of good advice. There is a book for every stage--I'm reading birth to three years. We turned to it when our son started biting, and it was very helpful.
Good Luck!