ROM issue

I'm just starting to learn the ropes here, so please bare with me. I have downloaded a rom. I'm pretty sure I downloaded an "iso". Here's the thing though...

I downloaded a zip file. When unzipped, it yielded three separate files that each contained the game name with different file extensions. None of them were .iso.
However, I put all three files into the epsxe "isos" folder and after starting the program, found only two of the selectable after selecting "run iso". Both of the files would start the game when selected. The file extensions were .ccd and .img.ecm. I'm sure someone here can make sense of these, but atm, they're greek to me.

Do I need all three files?
Would one do?
Should it matter which of the two listed above I choose?

Thank you for your time.

You need to uncompressed img.ecm
http://www.epforums.org/showthread.p...file-with-Gemc

If I choose "Run ISO" and select the file, it'll play....

Does it still need to be decompressed?

Oh, I understand now sorry. No it does not matter. One file is the binary the other is the music index. The emulator know what to do, just dont delete one of the files.

What emulator does this? I'm curious to know what emulator plays ecm files.

Its the ePSXe 190. I'm new, so may have misrepresented, but I think I told it right.

Thank you for your time.

yup it does in fact support ecm.