I think the temps are still within "normal limits" - the ambient temp seems to be 86, so that can definitely make things run hotter overall. Also, if it gets too hot, the iMac will shut down. As long as that's not happening, you're probably ok.
I know my Mac Pro at home often gets up around 130 or maybe even higher (I have it set to display the temps in celsius, so cannot be sure what I'm remembering!) under load - but I'm not at home now, so cannot check to see what all the figures look like in comparison to yours. In general, I think the components are rated to at least 194ºF for laptops and maybe as high as 210 for desktops (according to one site I read) so you're still a fair ways off that. Of course, excessive heat is always the enemy of electronics, so it's good to keep an eye on things.