Did you ever find out what was giving your PC so much trouble? You had some dozen or more posts but it was never clear why your PC had so many issues.
Bob
Some of them seem to do buffering and others OK, and some seem like chopped. I have the latest Flash player and have no problem watching video's on other sites, as I do here..ie..the review video area....why?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic