1: The sort of issue describe is common on ANY version of Windows if you try and install a service pack on a system with malware on it. A lot of malware worms its way into the OS so deeply that a major update like a service pack will ultimately render the system useless. So you should ALWAYS be sure your system is free of malware before installing service packs. This isn't some Vista thing. Far too many people with little to no skill actually diagnosing problems just decide it must be Windows' fault, and then because Vista got kind of a bad rap early on, people further refine it to be their preferred whipping boy. Anytime anything goes wrong on a system with Vista on it, it's always Vista's fault. Couldn't possibly be the pirated software with a hidden keylogger the user is installing, or the fact that the fans are so caked with dust and other crap, it's a wonder the system can turn on at all without overheating, but no... Somehow those are all Vista's fault, along with just about everything else under the sun.
2: Your particular problem sounds like one experienced by someone who didn't install the drivers post-install. Contrary to popular belief, Windows doesn't ship with this massive catalog of drivers, it's up to YOU to install them. So hopefully your computer came with a second drivers disc that you can now pop in and set about installing the drivers needed, otherwise you're going to have to go to another computer (like the one you're posting from) and download all the necessary drivers to a CD or flash drive, and then transport them to the other computer.
Recently, I tried to install some service pack update & it wreaked havoc on my computer. Apparently, it's a fairly common Vista problem. After fiddling around with it (it had basically frozen while installing the pack), the whole thing ended up wiping Everything clean & in the end, I needed the install disc to fix it. (which I *just* found)
So now I'm stuck on some "Welcome Window" & it's having trouble connecting to the internet.
What to do now?