What is it going to take to get Adobe to fix Flash so my computer doesn't turn into a camp fire everytime I go to YouTube?
Funny, I don't have the same problem as you're mentioning, but maybe my Macs are just better, including my G4 DP 1.25 ghz from 2002.
Here are some realistic solutions;
Download the latest version of Chrome(if you're on 10.5 or newer) -- It's a great browser IMO and Flash is now integrated. It has some nice built-ins for devs.
Download Flash Player 10.1 -- it should be released final now, or shortly, it's been in beta. It makes a noticeable difference in performance fo areas like video playback.
If you're on a notebook like either of the MacBook Pros here, you'll need to take extra steps for cooling. I use an app called "Fan Control" and a notebook cooler. My wife is on a Logitech-lap cooler and I'm using an Antec 200 on my desk and I have a Belkin for on the road. Apple's default setting for the fans are too low. I set mine to 2000 RPM minimum with the mentioned app. That coupled with the cooler keep my fans from rarely kicking on, even in Youtube. It also makes the top left of the MBPro always cool to the touch. This is assuming that you don't live where it's really hot.