SP1 for Visual Studio can take anywhere from a few minutes to several hours to install. Jon Galloway has collected some tips on reducing this time.
The first tip is to disable patch caching. While this will force you to have the original disks if you ever decide to uninstall the service pack, it will significantly cut down on the hard drive access and reduce the final size of the installation. Heath Stewart provides a batch file that will disable and re-enable caching.
The second tip is to uninstall C++ if you are not using it. According to Phil Winstanley, “the Service Packs will take minutes as opposed to hours to install”. Jon Galloway adds that occasional users of C++ can download it for free in VC++ Express.
The final tip is to wait until after you have upgraded to Vista if you plan on doing both. Otherwise you will just have to reapply the patch anyways.