I've done them both ways in the past but basically have moved to just doing everything at room temp.
Two things to remember: (1) you need a lot more yeast for a lager if you are going to ferment it at proper temperatures. My rule of thumb is 1.5 million cells per millilitre per degree Plato. (2) Since you are going to chill and decant the starter, you need to plan a number of days ahead. Enough time to ferment a four or five litre starter (for a 5 gallon batch, depending on gravity of course) then enough time in the fridge for the yeast to completely drop out. For an ale you can make your starter the night before and be okay; for a lager you need three or four days ahead IMO. You can shave some time off it but there's not a lot of point to decanting if you still have a lot of yeast in suspension.
Good luck!