The Microsoft System Configuration Utility, Msconfig (starting with XP), allows selective disabling of programs and services that run at startup. If your computer is unstable, runs more slowly than usual, or has problems starting up or shutting down, it can help you determine if a program or service run when the system starts is at fault. To launch it, do  Start | Run |  msconfig  | click OK.

All versions have a multitabbed interface to pick startup options. The General tab lets you select from Normal, Diagnostic (clean boot), or Selective Startup (you choose which items and services to load). You can also expand or extract files or launch System Restore from the Windows XP version of Msconfig.

Other tabs control settings in Msconfig, System.ini (legacy hardware), Win.ini (legacy software and configuration), Boot.ini and services (Windows XP), startup programs, and other version-specific startup options. Vista/7 versions eliminate the System.ini and Win.ini tabs.

Although it wasn’t part of 2000 by default, you can download it from the Internet, or copy it from XP, and it works the same in 2000.