Hi again, Derek.
1. portarse, comportarse: They're the same, I can't think on a sentence where they can't be replaced without changing the meaning.
2. causar, ocasionar: They're the same, too. We use causar more than ocasionar. But causa and ocasión are not the same.
3. discutir, argumentar:
Discutir is to have an argue with someone, usually we use discutir when you are angry with the other person after the argument. "He discutido con mi hermano": I had an argument with my brother (and now you don't want even seen him).
Argumentar is to give reasons. You are "argumentando" when you're supporting your opinion with arguments. For example "I think you shouldn't smoke, because it's bad for your health". Estás argumentando por qué piensas eso.
4. retraso, demora, dilación;
Retraso and demora can be the same when we talk about being late:
-"El tren llega con retraso" and "El tren llega con demora" are the same.
But retraso can mean to be behind schedule, to not have achieved what you should. I don't know how to explain it, I'll make an exemple:
-"Voy con retraso en los deberes de español": You still have a lot of homework, and you should have done it before. In this sentence you can't replace retraso with demora.
Dilación is the same as demora, but is not used. We use "sin dilación" which means "as soon as possible", but in other kind of sentences we normally don't use it. "El tren llega con dilación" sounds really weird to me.
5. ilusión, esperanza.
Ilusión can be illusion (something that is not real) but I think you mean the feeling. You feel "ilusión" when you're excited about something.
Esperanza is the feeling that something good is going to happen, usually we use it when we are in a bad situation and we hope things will be better.
-"Tengo la ilusión de que vengas": I want you to come, I'll be happy if you come. We use better "me hace ilusión"
-"Tengo la esperanza de que vengas": You're not here, and you probably won't to come, but I have faith on you coming