The # column represents how many hosts were found with that file. In your example: 22 have first, 3 second, 36 third search result shown.

Downloading from nn hosts mean that's how many people you are downloading from. But keep in mind, you may not be downloading from a complete file in all cases, but partial file sharing where someone who is also downloading the same file but has downloaded a greater % than you shares back some of what they downloaded (this speeds up downlding speed for everyone.)

Without writing a novel here, it's best you look at some stickies on similar problems. Music files changing to zip or exe: some info _ / _ Trojan posing as an Audio file

mp3 Bit-Rates Versus File Sizes (click on link)

BTW one problem might be the mp3 codecs you have are out of date or else don't cater for all mp3 types such as mp3pro. It might be worth checking out this page: CODECs list for Movies/Audio/ Alternate players / Video help forums/ video-mp3 fixers