That level of Castle of Illusion is
such a pita. Ugh, I get the willies just thinking about it. My 4 yr old loves watching me play that game and usually we turn it off about the time I reach that level so he doesn't hear any adult language come out of me.

The only other game that pops into my head right now is the last level of Air Zonk. It's stupid long. Getting there is almost a cakewalk compared to that last level.
And I agree with Lilgrafx, the last level of Blazing Lazers gives me pretty much the same feeling.