Switching a resistor ladder
I am looking to control this circuit with an mcu and would like
  suggestions of what sort of IC could be used as a switch


In this case your best bet would be to use digital POT, something like MCP4141 or AD7376. This one chip alone will replace all the resistors and switches and is extremely easy to control by MCU, with probably the smallest footprint possible.

For non-MCU control there are hundreds of miniature rotary switches available dirt cheap.