What are the Differences in between Windows XP Service Pack 2 and Windows XP Service Pack 3?

I'll just answer your questions first: 1) Yes, there are. I've personally tested it. Also, if you're a gamer, you might have even more problems as there are some conflicts between the updates and some video cards. They might have been fixed by drivers by now, but I still wouldn't recommend it. 2) "SP3 includes all previously released Windows XP updates, including security updates, hotfixes, and select out-of-band releases." So yes, SP3 is indeed better than SP2 when it comes to security. Although there are some updates that are really good in terms of security, you can't just rely on windows for that matter. 3) There might be. For some people it works better, for some, it doesn't. I personally thought it was exactly the same, the only difference being that I had some problems with it. 4) Bullcrap. You should always get the Service Pack for IT professionals. You don't have to be a big shot programmer to find use for it. Just get that, always, even if you decide to use SP 3. The lesser version lacks a lot of things. All in all, if you're not planning to use the PC NON-stop and for all sort of crap, like me, you can get SP3. But you might find some games not to work anymore, or you might come across some odd stuff. They say it's worth it, I say it's not. I like to keep it simple. If you're not satisfied with SP2, you can try it out, but I doubt it.

This statement is DIRECTLY FROM MS Windows XP SP3 includes all previously released Windows XP updates, including security updates and hotfixes, and select out-of-band releases. For example, the service pack includes functionality previously released as updates, such as the Microsoft® Management Console (MMC) 3.0 and the Microsoft Core XML Services 6.0 (MSXML6). Microsoft is not adding significant functionality from newer versions of Windows, such as Windows Vista, to Windows XP through XP SP3. For instance, Windows XP SP3 does not include Windows Internet Explorer 7, although Windows XP SP3 does include updates to both Internet Explorer 6 and Internet Explorer 7, and it will update whichever version is installed on the computer. For more information about Internet Explorer 7, visit the Internet Explorer home page. One notable exception is that, SP3 does include Network Access Protection (NAP) to help organizations that use Windows XP to take advantage of new features in the Windows Server® 2008 operating system