Every version of Windows, from Windows 3.1 and Windows For Workgroups to Windows eXPerience, has been full of flaws. From logistics and usability design problems, to security holes, to out and out instability problems, Windows has them. I help people with problems - it's how I got to be an MVP. The problems just don't stop.
Periodically you see somebody ask for help in an online forum, and as part of the system description, admit that they have one or more computers with Service Pack 1 (occasionally, no service pack) on their network. They all have good reasons for not applying SP2.
- I never got around to applying it.
- I heard too many stories about how unstable it is.
- My brother (cousin, neighbor, barber,...) told me not to apply it.
- It uses too many resources.
- I don't need it, it was just security enhancements, and my computer is safer without it.
- I don't need it, I can protect my computer without it.
- My computer is fine right now. You can't fix what isn't broken.
- ... and endless variations.
One of the problems with Windows, in general, is its stability and security problems. One of the causes of stability and security problems is the need for Windows to support multiple versions of different software, whether its own, or third party products.
Periodically, Microsoft issues rollup updates, which give it a baseline to work from when supporting their own product. SP2 was one of those rollups. By continuing to use Windows SP1, and by encouraging others to do so, you are requiring useless complexity in Windows.
Yes, your layered security, and your knowledge of proper computer use, avoids your need for SP2, within limits. If your computer is fine right now, and you don't plan to ever add any new hardware or software, you're only vulnerable to problems (and newly discovered security issues) in the current hardware and software. Maybe you can live with that. I'm not sure that I could.
What if you plan to add any hardware or software to your computer? Maybe one day the video card will die on you. Maybe you'll add a new game, or maybe a newer version of your browser, Instant Messenger, or audio / video player? Will the new hardware or software be tested for SP1? Will it even run under SP1?
All hardware requires drivers, that have to support the Service Pack. If you have to buy a new network or video card, can you find one that supports SP1? Take a look at Walmart next time you're there.
No software company has unlimited resources. Do you expect new software to be designed to work under SP1? Do you expect new software to be tested under SP1? For how long? How about the web sites that you surf to? Will they support your old browser, that supports XP SP1, forever?
XP SP2 has been out for a long time. Its time to put SP1 to bed, and prepare for SP3 or Vista, which ever comes first. As Windows customers move to SP3 or Vista, support for SP2 will continue. But support for SP1 should not.
Move to SP2. Windows is bad enough with it - its worse without it. And do it before you have to upgrade your browser, or install a new network or video card. Upgrading to SP2 is stressful. Upgrading to SP2 AND replacing your network card, simultaneously, will be far worse. That said, plan your upgrade, and fix all active problems first.