msconfig will get you the Windows built-in utility, but I highly recommend using the free app, Startup Control Panel. You can find it here >>
http://www.mlin.net/StartupCPL.shtml
You can download the installer or a standalone version. If you install it just type startup.cpl in the run dialog or double-click the Startup icon in Control Panel.
NOTE VISTA USERS: if you want to use the Startup Control Panel with Windows Vista please read the following (found here >> http://groups.google.com/group/mlin_net/browse_thread/thread/ba6050e5509fa53a/7337fa8f09f12825?pli=1):
Startup Control Panel DOES work on Vista, with a few notes:
RUN SETUP AS ADMINISTRATOR!!!
(step one only needed if you did not run as Administrator)
1- The installer does not work. Wait until it complains it
cannot copy the Startup.cpl file, and then manually copy this file to
the System32 folder. UAC demands an admin login at this point. After
placing it there it will appear in the control panel.
2- The control panel applet must be run with elevated
privileges. Just open it once and close it, Windows will ask if it
worked normally. Say it didn't, and accept the recommended settings.