If your looking for the difference if you trade in your wii it would be about a 100$ to 300$ depending on ps3 model or bundle. I hope I helped.
Yes you can - but it will not be a straight trade. You will more than likely have to put in more cash of your own for the swap.
No you cant only eBay can
No not straight away as the white wii is old than you have to pay a little bit of money for the black but at game they do it with wii sport resort and it is worth it
RE5 isn't on the Wii because it wasn't developed for the Wii.