Try opening it in a text editor, it may be junk or it may be something that was specific to however you managed music on Windows.
What is it called?
PS it's a bit risky to drop files onto Terminal & run it, you are safer using the 'file' command, it should try to tell you what type of file it is. Open Terminal, type 'file ' drop the .ini (to complete the file path) & hit return. It may not be much use, but it is safer than executing any file you find.
You don't need (and can't use) any file with type .ini on a mac.
They are somewhat similar to mac's plist files and other platforms' config. files, but they have absolutely nothing to do with whether you can play your mp3s on your mac. AFAIK, even Win 7 and Win 8 don't use them anymore, so unless you plan on going back to Vista, you can safely dump them.
It is called "desktop.ini" and it's in just about every folder of music I have. I didn't think it had much use but I thought it better to ask.
I opened it in textedit and this is what came up:
MusicBuyUrl=http://redir.metaservices.microsoft.com/redir/buynow/?providerName=AMG&albumID=F 8612E2A-C5FB-41D1-B4CA-45108CBACD0B&a_id=R%20%201069893&album=Riot!&artistID=3F8 F7C6E-F035-48C1-BD5B-3BA4DE0F7DFE&p_id=P%20%20%20729547&artist=Paramore&locale=4 09&geoid=f4&version=11.0.6002.18311&userlocale=409
It just looks like some metadata about where to buy the file, or that artists page.
I'd dump them. You could try a spotlight search to find them all in one go, otherwise the unix 'find' command has a delete feature…
Do a test first! - files to be deleted will be printed…
find /path/to/the/musc/folder -name 'desktop.ini' -print
Now the delete part…
find /path/to/the/musc/folder -name 'desktop.ini' -delete
The name is case sensitive unless you use -iname (ignore name case).
Spotlight is proably easiest, but I like Terminal :^)