It's better to check your CPU temp against your ambient (case) temp. At idle, a core 2 should be equal to the case temp (unless you've up'ped the voltage quite a bit). Either way, however, 29C is fine for idle temps.
Run Prime95 for an hour and check your temps. You shouldn't get above ~ 45C or 50C. That's the best way to check to ensure everything's installed and working properly.