sofaspud

Recently bought this nifty tool:

http://www.scantool.net/products.htm

Works fine. Thing is, I know little (alright, nuthin') about autos/engines
/mechanics (hey, I could barely drive). Anyway, if anyone out there
uses this or similiar scanner, can you point me to guide/site/whatever
that would explain (in lay terms preferably) the descriptions of the various
sensor data (screenshots: http://www.scantool.net/screenshots_features.htm)
AND what "good" values should be for an '02 elantra? TIA