As ADG said, you can be selective with your updates. You can disable auto. updates and run the "Windows Update" utility manually, every week or so.. Just be sure to choose the "custom" option over the "express", which will allow you to be selective about what updates you want to install...Whatever you do make sure you get all the security updates and hotfixes (which fixes OS bugs)
Whether or not you install updates automatically, I think it depends on how much bandwidth you have to spare. For instance, I regularly maintain my mother's computer with WinXP, which uses a dial up connection... She generally keeps her computer turned off when not in use... When she turns on her computer and connects to the Internet, first thing that happens (if she has auto. enabled) is Windows will go out to the Internet to find all those updates which will, in some respect, monopolize her connection.... I also, keep her anti-virus definitions from being automatically updated for the same purpose.. Try to imagine your anti-virus updates and Windows Updates going at the same time over a dial up connection, on top of all the fluff ISP software that may be installed on your system
You may not be using a dialup connection, but you can use this a sort of a reference..
