Equihash and Library are faster on Nvidia cards, Ethehash and Cryptonight are faster on AMD. There are more algorithms but you can google those and decide which coins on those you would like to mine. You can also look at sites that give known hash rates for different cards and use calculators to see how much you'll make.

 If you're focused on short-term profits, how much you make in dollars or euros or whatever your currency is, would be more important. If you're hoping to take a bit more risk and win big, find a coin you think will be big and having more coins is more important than dollar value today.