is there an LDR you recommend in particular
NO particular LDR in mind, the way you connect it is described in - Arduino Forum -
If so how is this connected back to the board.
TO connect an LDR correctly it must be part of a voltage divider
+5V ---- [ LDR ] -----* ------[Resistor] ----- GND
Connect analog port of Arduino to * in the middle
The valueof resistor must be in the same order as the LDR when in the dark. (a 10 K will work probably too)
Thanks for helping out an amateur here!
I cant wait to see the curtain work, (post a youtube when ready ?) you just added a new dimension - inflate - to what to do with Arduino 
I can imagine that such inflatable curtains help to keep out heat during the day and let in fresh air during the night.