Unable to download readable rom files forDolphin?

Hello.
I'm unable to download readable rom files for Dolphin. I'm only able to download .wbfs and .rvz files. I'm un able to download a .ciso file, as that doesn't show up.

what's more, when I do download .wbfs or .rvz, it's actually downlaoded as a Window Media Player file?

Any idea on how to get the right file for Dolphin roms?

Thanks in advance!