on a single Gold account?

or does it have to be a parent account?

Only the Gold Account can play online.

However, you can create up to 4 more accounts and each of them will come with 1 month Gold for free.

If you want to play Halo 3 splitscreen online for example, the secondary player needs to sign in as your guest, then you only need one Gold account.

Even if one is a Parent account? , thats pretty lame if you ask me...

what about when i have a Parent account , it said Xbox live online is allowed , but do i have to be gold on both parent and non parent account?

You can create a parent account wtih 3 sub accounts for 99 bucks a year.

All the points and memebership stuff has to be distributed through the main account to other 3 but all 4 accounts can go online separatly...

Most games that have split screen support online coop play and you can bring the second player as a guest.

Are you talking about a family package, or saying you want free gold for anyone that uses your 360?

No if you want people to play Halo or something on your box just sign them in under your guest.