I read some of the above posts, but they ALL seem to be right in each way.
Lifting weights increases both your Power and Strength, what do you want? Both of course.
There are two types of muscle tone you need for both. Dense, tight, compact muscle for power, and big, larger muscles with lots of blood flow for shear strength.
You guessed it, there are 2 types of work outs that address each type of muscles build.
To make power muscles you need to do maximum lift and your best reps. (increase both weight and reps as you can).
To make strength muscle you need VOLUME (big muscles), to make big muscles you need MAXIMUM REPS and best weight. **(increase both as you can).
All of the above implies you eat a very high diet in protein, amino acids and give your muscles times to heal.
Edit: **