ADC Interrupt for temperature sensor

My application is to display the temperature value on the LCD, sensor is PT-100, this sensor has a resolution of 3 ohms per 10 degree change. So single ADC read (what i use in my code) gives a wide varying temperature value displayed on the LCD. eg: 29,32,26 etc.

My plan is to use a ADC conversion complete interrupt where i shall take an average of 10 readings and then display it. Can you please help me how to use the ADC conversion interrupt ?

Example program 'Smoothing' has similar averaging concept, but it is inside the loop. I prefer to have an independent interrupt routing instead of continuous reading.

Thanks
Ramesh

This might help

http://openenergymonitor.org/emon/buildingblocks/rtd-temperature-sensing