As music videos occupy a lot of space on your hard disk, keeping just the songs and not the images could be a more efficient solution. Programs like AoA Audio Extractor are designed to help you with this task.
This basic version will bring you a small number of simple output configurations, therefore, any user would be able to manage its intuitive interface. You will be able to extract the audio content from the entire video or just certain sections from the input file.
A nice advantage of using this audio extraction tool is that it delivers the results in a minimum time.
Personally, I would like to have more options for the output format selection as the application only offered me three alternatives: MP3, WAV and AC3. Plus, the program lacked a help manual and a built-in multimedia player (I was unable to check if the selected section from the movie clip was accurate).
A thing you should take into consideration while installing this application is that it will offer you to install some unnecessary tools. Be careful to uncheck these options if you want to save some free space on your hard drive.
To summarize, the program managed to extract the audio content from my videos and the results weren't bad at all. But, the fact that it had such a small number of output configurations available, to some users, might come out as a relevant disadvantage, even though you don't have to pay to use it. Therefore, it's up to you to decide whether it's worth trying it.