The information displayed in the Summary Screen as CPU voltage is the internal view of CPU's VID value. This depends on CPU model, some CPUs do not offer the capability to view VID values (Operating Point Protection on Nehalem, etc.).
CPU Vcore voltage displayed in the Sensor screen comes directly from the sensor monitoring chip (in case it monitors the Vcore rail).
However, the sensor information might require special adjustments per a particular mainboard in case it's not directly supported by HWiNFO32. If you feel the information is incorrect please submit report+DBG (+BIOS screenshot of the Health Status) and I'll try to adjust the information to correct labels and values for that mainboard.
Some information in the sensor screen might display invalid values, which is caused by the fact that a particular mainboard's sensor doesn't have some pins connected to real inputs. Again, this situation requires motherboard-specific adjustment to be performed.
Would like to know how accurate the temp/volt readings are.
Furthermore when I run the program I'm getting 2 screens : System summary which gives info cpu status VID reads 1.325V.
If I take the second screen at "sensors" however I'm getting a Vcore reading of 1.44V. Which is correct. Changes the voltage of the cpu in AOD to 1.325 but Everest also reads 1.44V.