Venus ranks No. 1 for average temperature because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead (3,280 degrees Celsius). Don't try to visit.
Mercury rotates slowly and has a thin atmosphere, and consequently, the night-side temperature can be more than 5,000 degrees lower than the dayside temperature. On Mercury, you either freeze or roast, period.
Earth, well, you know.
Mars is mostly frigid, as low as -189.67 degrees Fahrenheit (-123.15 degrees Celsius), but during daytime near the equator, temps sometimes reach a comfortable 80 degrees. Because the red planet has only a very thin atmosphere, the temperature plummets at night.
Temperatures for the gas giants (Jupiter, Saturn, Uranus, and Neptune) are shown in this chart at a level in the atmosphere equal in pressure to sea level on Earth.