This is exactly what i was looking for here.
http://en.wikipedia.org/wiki/OBD-II_PIDs
You can get a better understanding of the readings on your ride.

Here is some good reading. It explains everything very well, but its a lot of reading. Its a good start.
http://groups.engin.umd.umich.edu/vi...ganesan_w2.pdf

Here is good site for information on trouble codes.
http://www.obd-codes.com/