To go back to one of your original questions, in Speedfan, your temp 1 looks like your GPU temperature. Not sure if this actually comes from the GPU or from the Northbridge but your reading looks similar to mine.
The temp 2 looks like your Tcase temp. Easy way to check this is look in your bios settings and see what temperature it is reporting (the temp in bios usually reads Tcase).
I don't use CoreTemp - had some problems with this. If you want a second or verifying data on the core temps. I would recommend the Intel Thermal Analyzer Tool (TAT).
For comparison, I am running a E6600 with a Zalman 9500 HSF, and slightly overclocked to 2.8GHz (no voltage increases ~1.32 Vcore). My idle temps are around 31C on both cores and at 100% load temps (using TAT) around 58C.
Echo bobjmoran comment, read the link in his reply. It provides a great guidline on temps.
Hope this helps...