npo good
NPO are good also, but in these high values are big and expensive if you can get them at all. The higher the capacitance for a given physical size the worse they are for noise generation caused by the piezoelectric effect.
The various poly types have individual properties that are not important in your application, such as temperature coefficients. If you use leaded parts, remember that the lead end that has a band around the capacitor body is the outside foil. This should be mounted in the circuit towards the node that will produce the least noise problem from capacitive coupling to the outside world. This is usually the lowest impedance node of the two.
There is a McGraw Hill handbook of components. Capacitor manufacturers should have application notes on low noise applications. Ott wrote a famous book on low noise electronics. These may be available at a local library.