Firstly start them off inside till there about 8 inch, that will give them a better chance against bugs n shit. Keep a fan on them so they get strong in this time, dont want to find them snapped after 1 day :P.
Onto location - on hills they its more likely that mold will occur while flowering (not certain just more likely), however id put some on that clearing you were on about. Direct sunlight is going to be the best, i think in your location have a clear south (plants facing south) but if im wrong just keep an eye on where your going to plant and see if the sunlight is good. Spread your plants about if possible (asuming your not going to be carrying a shit load of water to locations far apart), use it as a opertunity to experiment, after a few grows you will know which spot is the best and do most of your growing there.

Strains - white widow is an indoor plant, arnt the biggest of plants. go with a sativa, or a sativa dominant strain, cos its all your land doubt anyone will see a big ass 7ft beast in the right location

Amount - Because indoors space is usually limited large plants are usually out of the question, people tend to go for a indica dominant strain (WW northern lights etc). youve got all the hight in the world and a sativa will get bigger than you hopefully the cola will be half the size of you, and if your one of those really little people maybe as big lol. Thats alot of bud.

hope this info helps, the skiing arab