Finding Q for filters
The formula you have corresponds (once rearranged) to a 2nd order low pass filter: -

\$ H(s) = \dfrac{\omega_n^2}{s^2 + (2\zeta\omega_n)s + \omega_n^2} \$

So divide thru by \$ R_1R_2C_1C_2\$ and then you have all the bits in place.

You'll be able to see what \$\omega_n\$ is - the last term in the denomitor is \$\omega_n^2\$. The zeta (\$\zeta\$) symbol is the reciprocal of 2Q. So take the 2nd term in the denominator and divide it by \$\omega_n\$ and then rearrange to find Q.