I normally do not have Windows Sounds enabled; after a while, they become a little annoying. But a greater annoyance is the PC Speaker; when sounds are turned off, you’ll often hear beeps coming from your PC. Here is how you can disable them in XP/Vista/2003/2008 using the Command Prompt (Run->cmd):
Temporary: net stop beep
Permanent: sc config beep start= disabled
Note the space between start= and disabled.