Sony's are way overpriced IMO for what they come with, unless you find a killer deal. They are nice machines for sure, but you are paying for that Sony badge. I have used a Sony, the ultra small purple ones they made back in the day and while it was nice, it wasn't anything special, except for the size. Think laptop taping. I would recommend a Dell XPS model for power and features. They also have their own support tier specifically for that model. HP and Toshiba also make great laptops. Several manufacturers also offer a downgrade to Win XP as well, but it might cost a little more. Little harder to find, but they do exist. You do not want to spend more than $1500 max on a top of the line laptop as they lose value FAST. Support should be one of the main things you consider. Some companies offer on-site (home) repairs the next day and/or next business day replacement should something happen.
I use a Dell XPS m1210, 12.1" screen and it is PERFECT for school. VERY lightweight, small, etc. Of course, a 12.1" screen also makes it a little harder to do some tasks requiring a big screen, but for my use it rocks, especially traveling around to shows. The XPS 1330 is a 13.3" screen which is also a pretty damn nice upgrade to mine (newer model) and is SUPER lightweight. There is also the XPS 1530 with a 15.3" screen. I have not seen one of these in person, but I imagine it follows the rest of the XPS line, although bigger and heavier. Staples carries some of these so go take a look in person. My biggest mistake buying my first laptop was spending WAY too much and not taking size and weight into consideration, but I had to have the most badass one out there at the time.

Good Luck whatever you decide to do!