I'm not trying to be a dick, but I doubt anyone will want to take the time to price all those items for you - that's quite a lot of work. The price guide here will give you an idea of what to expect for you Neo stuff, but you'll probably have to do most of the work on all your other games.
If I were you I'd keep them and find another way to get the money. Most of them are either common or not worth all that much, but you've got some really enjoyable stuff there that I'm sure you'll miss if you dump it. Just my opinion.
Well, it depends. What condition are the games in? Are they all complete?
I would suggest just looking stuff up on eBay. That's probably the best pricing guide around. Oh, and if you plan on auctioning this all off, I wouldn't do it all at once.