The approach you are looking at seems fine to me, you didnt explain what the whole design is for. If you are just making a basic temperature monitoring sytem covering a limited range only, then I would stick with what you have now. If you are designing a more flexible system for doing other things then generally you need to add optional gain to the circuit.
I know you realise that 4096mV is 1mv per step resolution, so it is easy to work out what you get on your thermistor in this application, however if great ranges are required then instrumentation amps start to offer the benefits. I preffered the Burr Brown (now TI) range due to their low power requirements.
Instrumentation amps offer benefits in precise gain, common mode rejection and ability to run from dual/single supplies. It is also possible to get the inputs/outputs to go to within 100mV of the rail supply.
Just one other comment, I take it you are running fairly short cables for the thermistor ?
If running longish cables then consider the use of constant current supply rather than a voltage divider.
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