Downrigging Freshwater Salmon/Lake Trout Questions

I finally bought a boat for our house on Lake Winnipesaukee, NH this
year. I've fished all my life, but primarily for trout on rivers and
small lakes/ponds from canoes and row boats. I never had the need to
use downriggers or trolling gear before.

I outfitted the boat with 2 cannon lake trollers. I plan to fish the
land locked salmon and lake trout Winnipesaukee and the surrounding
lakes offer. However I have a few questions.

When fishing for landlocked salmon, what baits work best? I've picked
up some Mooselook wobblers and trolling spoons. But what about live
bait on downriggers?

The average size salmon is about 2 - 4 lbs. What size downrigger
weight and release clips do you reccommend?

With the water still cold what kind of lures/bait do you recommend for
fishing the top of the water?

I have several spinning rods, varying in lengths and action. I planned
on using some 7' medium action rods with 8lb test for downrigging. Is
this about right or is a downrigging/trolling rod necessary?

Any other comments or suggestions are greatly appreciated.

- Dave