I have become convinced that Windows service packs and childbirth have a lot in common. You approach the big day with nervous anticipation, and hope that everything will come out OK. That day sometimes involves a lot of pain, but a few years after each event people look back wistfully and think, "Gee, that wasn't so bad. I'm sure glad we did it." As the big day arrives for Vista Service Pack 1, be prepared for that short-term pain.

Indeed, the pain already has started. One of the prerequisites for Vista SP1 was put into the Windows Update pipe last week, but was pulled after many people reported problems. On one of my Vista systems, this update is just stuck. It won't install but it still insists on another try each time I restart the system.

Early adopters will experience the worst of the pain. (Adopters? There's where the whole childbirth analogy falls apart, I guess.) If you think you might want to jump right on the service pack when it becomes available, be sure to check out the list of programs that won't work after you install Vista SP1. Microsoft has intentionally disabled several common security suites (BitDefender, Trend Micro, and ZoneAlarm) due to what it describes as "compatibility problems." If you install SP1 before checking for a compatible update from one of those vendors, their problems will become your problems.

Like most major changes and updates to Windows, the best plan of action is to hold back for a month or so until the full extent of any problems becomes clear. That also gives third-party vendors a chance to get serious about fixing problems that crop up. Vista SP1 fixes more than 300 problems, including several performance issues; it's not a question of if you'll install it, but when. Windows XP SP2 was a major and disruptive change to Windows, but in retrospect it was the best thing that ever happened to XP. In the meantime, I will prepare for XP SP3 and get an epidural.