(Vista) WMP11 appears as a dot on the webpage for streaming

Hello, I use Visata home basic with WMP11 (the newest version).
I watch many streaming videos on websites and forums, and just last night,
all of sudden, whenever I try to watch streaming videos, the media player
appears as a dot on the webpage just as when you try to load a picture with a
broken link.
I didn't change any settings on WMP and the websites that I go are used by
millions of people and I've used it since 2007. I did install one new
program, but this one is non-wmp related whatsoever. I first thought it was
add-on problem so I deleted and re-added WMP add-on and I even deleted new
program and checked firewall. Then, I googled and checked other computer geek
sites for help, and all of them told me to either reset the registry of WMP
or delete WMP11 and reinstall it. Since I'm using Vista, I can't find
Run/Execute DOS window anymore, so I can't reset registry, and since I'm
using Vista, I can't delete WMP11. What should I do? Please help. I'm so
frustrated. (I also upgraded WMP11 and Internet explorer and everything)