The 360 slim isn't an upgrade, it's a new console release. You can however try GameStop or entertainmart and see if you can sell your old 360 to help split the difference for a used 360 slim, this is what I did when upgrading myself from original xbox to a 360 elite. Or you can sell your old 360 for as much as you can get for it without going over it's original price (or you can try ebay.com if your the appropriate age, that can help get a good price too and perhaps go over) Then use that profit for a new 360 slim.
You can trade the Xbox 360 for store credit, and with that you can put it towards the new Xbox 360.
you can.
Probably not, but you can trade it in for money, and use some of that to buy an Xbox 360. The main reason for this is that the PS2 is not as high=profile and new as the Xbox 360, which is considered a much better console. If you want to trade something in for an Xbox 360, it should be as high-profile and desirable as an Xbox 360 itself.
I would trade a ps3 for a xbox 360
you can trade an xbox elite into game and get half price of the new xbox360 ! but you cant trade it and get a free one.
Maybe for an Xbox not a Xbox 360
No. You can trade in your xbox for whatever they will take and save money to combine until you get a 360, but you can not turn a regular xbox into a 360.
No.
yes they can on another or new xbox 360
Sure if you add the the money for a Xbox 360 minus $20
Yes. It doesnt mean that you will get the Xbox 360 for free though. i know that but how and where
New games do work on an Xbox 360. This is, of course, as long as they are specifically Xbox 360 games.