Nowadays, there are custom miners for Bitcoin. These use customised hardware (ASICs) and thus GPU mining is not profitable. However, this custom hardware does not exist for Litecoin and most other altcoins (based on scrypt). Thus, you might still be able to make money GPU mining Litecoin this way.
Unless you have customised hardware, forget about Bitcoin mining.
The other contributors are correct though - doing this on a laptop is probably not a good idea anyway, but you'll still make more doing Litecoin than Bitcoin.