Nice one.
1996 rates at 87%, good, but not great.
Now it really depends on what you want to do.
To be anywhere near drinkable this needs another 15 years at least.
As to value well depends on where you sell it.
Honestly it wont of gain much value as yet as it wasn't a great vintage.
As to where to sell it, well Sotherby's holds regular wine auctions.
Sotheby's - Welcome
Here's some ideas of current prices:
1996 Margaux Bordeaux France : Wine-Searcher.com