[quote name='au7oma7ic']yea, I guess, I don't know what you mean by this?
I have not used my xbox live account forever (dont like paying money for this). But, once the game is downloaded onto the HDD it stays there for good, unless the person wanted to erase for some reason. However, on the HDD I am not erasing anything for the seller, so he/she can choose what to erase, meaning the profiles etc will all be on the HDD.
But the DLC will work without a problem, as it is connected to the account (which is included) but also since it was directly downloaded onto the HDD[/QUOTE]
If you just put the HDD on another system it will not work. If you try to play the arcade games on another system with a different profile you are just going to get the demo. The DLC is tie to 2 things, your live account or the system. So either
1. The system
2. Your live account when it is connected online. Offline will not work.
So you will need to include your live profiles and the person needs to be online with that profile for the DLC to work. You are probably want to give out the password and email for the buyer as well. The person also cannot use his own account when using the DLC.
If you google Xbox 360 DRM problem you can get more info. Personally I would sell the HDD and system together, that way the buyer can use the DLC with his profile as well as using it offline