Problem with upgrade to 2.41

[faithpro]

I recently upgraded to the 2.41 professional version. Since the upgrade, saving my movie has taken hours instead of the 10-20 minutes it used to and i've been having problems with video quality. When I view my finished product on my computer it is clear, but when I upload it to YouTube, the first few seconds are blurry or pixelated looking. It doesn't happen with every video, but is happening with most. I have tried private browsing with Firefox to see if that is the issue and it did not help. I'm saving my movies in the same format as I previously did as .mov file with 1920 x 1080 HD resolution. Does anyone have any suggestions for help?