How much do you think people would buy this for on ebay?

Although it is a LOT more trouble, you will get significantly more overall if you sell each game and gaming system individually. Some people make a living buying this type of thing in lots then selling them individually. If getting the most money for your stuff is important to you, you should take the time to list each one individually. If you have one that you don't think is worth much or anything, you might consider paring it with something more valuable just to add some value to the other item. If your main purpose is to just clean house and get a little money out of it you may want to sell in a lot.