Moon shot advise
Well doesn't it depend on what kind of shot you want? If you want a wide angle shot with a reflection of a whole lake/pond, then you might want to use the Sigma.
If you want a vertical shot emphasizing the moon and its reflection, a narrower lens will do you better.
As far as settings, I'm pretty sure you won't be able to expose both the foreground/landscape AND the moon properly with one exposure, you would have to stack a couple different ones to either keep the moon from blowing or the land from crushing.
To get an exposure for the land, just set into aperture priority, spot metering, and set the lens to f/8 or the like on a tripod for a good long exposure. To meter the moon, you may have to do it manually, as I'm not sure you can move the metering spot around.
Good luck, I hope to find a place to get a few good shots myself, moon will be its biggest this year on Saturday!