Daisy chain Thunderbolt display to regular, fullsize DisplayPort monitor?
From Apple's Thunderbolt Ports and Displays FAQ:

Can I connect a Mini DisplayPort display to my Apple Thunderbolt Display for computers that support using more than one display?
Mini DisplayPort displays will not function if connected to the Thunderbolt port of an Apple Thunderbolt Display. Displays connected via Mini DisplayPort video adapter or cable to the Thunderbolt port of an Apple Thunderbolt Display will not work.

So as you guessed, you can't daisychain a non-Thunderbolt display to a Thunderbolt display. You can only do it with two Thunderbolt displays (or of course, two displays on different ports directly connected to your Mac).