As far as I know, yes. They look at all your grades from Freshman Year through junior Year, and Senior Year mid-year grades as well. But obviously, freshman year grades don't hold as much weight as junior year grades. If your freshmen year grades are a bit low (mix of As and Bs), it's OK, as long you show an upward trend. (i.e. your grades got better from year to year.)
I'm sure they look at them, and I'm sure if you get more than a few B's or A-'s your chances are going to be hurt. You're going up against the top 0.2% or so of college applicants across the country, so everything matters to some degree. This being said, my SAT scores weren't that good, so I think everything depends on how well you market yourself. Work hard and don't slip up again.
My thought process is that, if you're going up against an identical applicant and the only thing that is different if your freshman grades, that may cause a difference in your fortunes. I would take everything an adcom says with a grain of salt—everything matters in college admissions at this level.
Why don't you do some research (NOT on CC) before you ask this question..? I'm sure it's somewhere on their website; if not, contact an admissions officer yourself. If anything, they'll be happy that you're taking the initiative to ask questions and learn more about the school. Plus, that opens up a thread of conversation between you and an adcom.
We will focus our evaluation on your choice of coursework and your performance in 10th, 11th and 12th grades, mainly in the core academic subjects of Math, English, Social Studies, Science, and Foreign Language.
In all technicalities (just to resolve this question), even if Stanford doesn't look at Freshman grades (like UC's), they do. Not directly at the grades during freshman year, but the rank / percentage tier you are in (for example, rank 23, in the top 10% etc). Since your freshman year for most high schools is considered in the ranking/percentage system, it is in all sense "counted". Thus, it is advised that you try not to mess up freshman year.