Ways to say "have" in japanese?

Question:

motteiru? motteru? motte imasu? I don't quite get it.

How would I say these then?:
"I have MSN"
"I have homework"
"I have a pet dog"
"I have the time"

There would be a difference in all of them because of the 'objects' right??

Answer:

motteiru, motteru and motteimasu both means the same thing.

motteru is more casual speech, motteiru is the normal form while motteimasu is the polite (teinei) form.

I have MSN. MSNを使っています。MSN wo tsukatteimasu.
I have homework. 宿題があります。Shukudai ga arimasu.
I have a pet dog. 飼い犬がいます。Kaiinu ga imasu.
I have the time. 時間があります。Jikan ga arimasu.

In your 4 sentences, it's much more normal to use aru or iru, then motteiru.

The times I'll use motsu would be,

あの人に興味を持っていますか？　Do you have an interest in that person?
母はちっちゃいな店を持っています。My Mom has a small shop.