If that 3.6 is an unweighted GPA, it looks like you have a good shot. Academically speaking, your GPA isn't exactly on par with the average Stanford student, but being a nationally ranked squash player can definitely help you stand out in the admissions process.
Unfortunately, being starting high school quarterback, while a terrific accomplishment in itself that you should be very proud of and (by all means) should put it down on your Stanford app, won't really help you stand out unless you are being SPECIFICALLY recruited by Stanford to play football. Stanford's athletic program is excellent; they have won numerous championships/ made numerous appearances at the Rose Bowl throughout the years and twelve alums are currently playing for the NFL. To become a recruit your high school team must have won State Championships, be nationally ranked, etc. If you are interested in being recruited or think you can be, try setting up a free profile at BeRecruited.com. This will let you get a lot of exposure to different coaches/ schools, even if it's not Stanford.
It sounds like you have the beginnings of a really great application to Stanford. They look for passion in extracurriculars, which you have in athletics, so that's a great start. They also look for intellectual vitality-- it is their most important factor in admissions-- how do you think, analyze, etc.? Make sure you dedicate yourself to your essays and let your voice shine through.
Unfortunately, plenty of applicants with 4.0+ GPAs, 2300+ SAT scores, and awesome extracurriculars are turned down by Stanford every year. With 35,000+ apps and space for a freshman class of only a couple thousand, competition is stiff. The Class of 2013 faced a daunting admissions rate of only 7.6%. So even with your squash rankings and football talent, you cannot be guaranteed admission.
Do what you can: Invest time in what you love, focus on your GPA, challenge yourself with AP/Honors classes to get that GPA up!! I'd say you have a shot at Stanford, just like anyone else-- if it happens, that's wonderful, but if not, there are so many other terrific schools that would love to have you attend. Good luck.
Erik Kramer
Their starting quarterback Ben Roethlisberger.
NFL player R.J. Stanford played for Utah.
NFL player Julian Stanford played for Wagner.
Terry Hanratty.
NFL player R.J. Stanford weighs 190 pounds.
NFL player Julian Stanford weighs 230 pounds.
NFL player R.J. Stanford is 5'-10''.
NFL player Julian Stanford is 6'-01''.
Any player, including the quarterback, may return to the game at any time if they are replaced by the coach.
That 'C' on a player's jersey indicates the player is one of the captains of the team. Almost always in the NFL, a team's starting quarterback is one of the captains of the team.
Any player on the opposing teams defense is allowed to sack the quarterback.