Small Engines (Lawn Mowers, etc.): Craftsman/Briggs 6.75 HP wont start, winter thanks, white smoke


Question
I have a 6.75 21" cut, front-wheel power mower. It's only a couple years old. I think I have an inkling of the problem, but want to make sure it is as simple as I think.
Took it out of the garage to cut the lawn for the first time, and the engine won't turn over. Doesn't seem to have a spark, although it sputtered some white smoke and tried to run at one point.
Is this just tired gas and a fouled sparkplug? Or could there be something more serious wrong. Haven't had a problem with it in the 3 years I've owned it. Good mower, but sits in the winter.

Answer
Thanks to the god old EPA fuel quality sucks!
If it had fuel in it over the winter you need to start there.
Lets go over some terminology before we go any further.
Engine won't turn over means that the engine will not spin.
No spark means you took out the plug and grounded to the engine and pulled the rope and there was no spark at the plug.
I assume the engine does turn over and it must have spark or it would not sputter white smoke.
White smoke  ALWAYS means burning oil. Clean the carb and tank and replace the plug and air filter. The oil must not be over the full mark.
Do these 3 steps and you won't have to buy a goat.
Doing these steps repairs 90% of all mower problems.