Nick, I tried to follow your directions. I went to Tools and there were no Folder Options and no tabs for File Types.
I managed to get my computer to play radio4.nl by trying a lot of things almost randomly and repeatedly. I made Real Player my default player. It has Radio with a record of what stations you've listened to recently and allows you to choose more stations. Radio Player just ignores the video option and plays the streaming web station, radio4.nl.
I still want to figure out how to set my preferences. My toolbar must be different from yours, but that information has to be on my computer somewhere. Grrr. Frustrating.
I thank you for all your help.