There is a procedure to turn Windows features on or off but system sounds are not one of the options. The "no sounds" option is the only thing available, without deep knowledge of the OS to disable any sounds.
There are some programs that have their own sound schemes and possibly one of those is causing it. Look at what is in the startup, maybe something there is causing the sounds. Messenger type programs, Skype or similar, e-mail programs, etc.
Bud Isaacs and his recording of "Slowly" with Webb Pierce is probably the most influential pedal steel guitar recording. There were pedal steel guitars around before this but that one recording was the breakthrough that all other steeler's cite as the inspiration to play pedal steel. I met him at the International Steel Guitar Convention in St Louis when he was inducted into the Steel Guitar Hall of Fame.