Then right click on the volume icon at the bottom right on the taskbar.
Open the volume control
Choose options / properties and select the volume for recording,
Select mixer .
Check on the window control recording mixer is selected.
Then prepare audacity to record the sound.
Prepare the clip, or other program that produces the sound you want to record.
Run and start recording what you want to record.
Stop the recording when you have captured or sounds you want.
Finally, in Audacity, select the filename and the format in which to save it.
Using Virtual DJ
You can save sound using virtual DJ to mp3 format. Go settings and choose your sound quality then press record to start recording sound playing on your pc.. Example ( you want to save a soundtrack from a movie )