I took my heads off today to replace the head gaskets. Can anyone tell me why one of the valves is so tan and another seems very dirty. This is the first time I've ever been this far into an engine so I was just curious if this could be a more serious problem or not. Also what would cause a push rod to bend this much?

 

The valves look pretty much within the "normal" range, to me. Nothing unusual.

The center cylinders in a carbed or TBI (wet-flow intake) motor tend to run richer, and color the exh valve more; the end cyls tend to run leaner, and color them less. Looks like basically what you've got there.

Bent push rods in a stock motor are usually the result of over-revving. If the motor isn't stock, they're usually caused by poor valve spring selection.