Well if I turned off IE8 and Windows Media Player, I'd get higher scores too, as those two applications are the source of my problems. But that's not what you're supposed to do. This just shows the weak links in the chain. Although it's true my applications have closed up once in awhile, this isn't a fair test as it doesn't show the amount of time the computer is in use, which is 15-18 hours a day, under heavy use. If I only used it a couple a hours a day, my score would probably be much higher.
So even though my score looks bad on this graph, it really isn't too bad as I'm only getting a handful of problems that happen on rare occasion. I'd rate my computer as about 99% reliable, with a less that 1% problem rate. That's pretty good...