I stayed there in Jan and Feb of 2003. I stayed on points, and got an upgrade to the C-level. The lounge is very nice, and they had excellent choices in the morning and afternoon. There were a few nights where I just had C-lounge snacks as dinner (I too, was a kid on a budget... well, maybe not a "kid", but definately on a budget).

Here's a good thread on things to do in Santiago: Santiago weekend.

For the Concha y Toro winery tour, you go to the Bellavista station on the subway, and then grab the number 80 bus. Reservations are recommended. I got in without one because I was a single.