temperature gauge

[Elven Commander]

Hi all,

I've made alot of progress on my project.  I have a working display unit of 3 7 segments, and am kinda working backwards.  I have all the driver/decoders connected, and all those have a decade counter(sp?) connected to it.  I am at the point where I am a bit unsure of how to proceed.  I am using a thermistor.

 
          I know i must somehow compare the voltage to a base voltage and if it is below it is -'ve or above being +ve. 

              I have read about a comparitor circuit I think it is called
2 capacitors in series across the 2 inputs, and then 2 resistors, the top resistor is the thermistor, and the bottom would be the standards room temp value ie 1.2k.  Then the output is from the bottom of this which is ground, and from inbetween the 2 resistors which is the +'ve voltage.  Am I right about this???  how do you know what kind of capacitors, do you just use the max voltage that goes into your circuit? and what kind of power would you use for this?

My major question, is if this indeed works, how does it make the leap from a change in voltage to