"Can't download episodes from your feed" - no idea what I'm doing wrong

The URL given for your media file is feedproxy.google.com/~r/4screenandcountry/~5/vbICOD6aCeo/open (http:// removed so that the forum will show the URL not the title). Feedproxy is dodgy where podcasts are concerned, and in any case iTunes can't recognize files without the extention - .mp3, .,4a etc.

This redirects to a Google Drive URL which is a web page with an embedded player - this won't work: you must provide a direct link to the file. You need to find somehwere else to host your files - Google Drive simply doesn't work with podcasting. The URL must lead directly to the file, it must show the extension, if you enter the URL in a browser the file must play directly in the browser, not download, and the server must support 'byte range requests' (the method used by iPhones to download files), something you'd need a proposed host to confirm.

I don't have experience of them - I used my own webspace for my podcast. Any ordinary webspace will do, provided that a) it accepys byte range requests and b) will cope with the traffic if you get popular: normally this would be paid-for space though you may have some bundled with your internet connection (though this is becoming rarer).