Well I would suggest making sure that you keep Vista up-to-date with all of the security patches and bug fixes released by Microsoft, so schedule and/or run Windows Update application daily. As far as making the operating system faster...don't listen to n00bs telling you to disable Vista's Aero feature. That's what most people say slow down the operating system [and really it only slows down the OS if you have a crappy video card]. You can try making Aero perform faster. There's not much you can do to accelerate an operating system though. Hardware plays a significant role - definitely have at least 2GB if not 4GB or more of RAM if you can afford it. You should have no problems with speed. Always keep your PC fast by running disk clean-up, LavaSoft AdAware, SpyBot Search & Destroy, PC Tools SpyDoctor, and CCleaner (search Google for downloads, all are free software) regularly. Also defrag your hard drive once in a while..you should have no problems.
Windows in general sucks, the reason is that it is the only operating system that is forced to include DOS inside it and DOS is acient now and just laggs up the system and Vista is just so unreliable and overpriced, seriously its so bad that its older version (xp) is better than it, also 90% of developers are only writing apps for xp so good luck with all the apps that dont work on vista, becuase all laptops nowadays come preinstalled with vista I am going to buy an older laptop and install linux, it will be just as fast and 10x cheaper. Shmoe