Based on your photos, I can speculate that photo 1 shows a poor use of road salt by your municipality and/or the homeowner—it looks like a snowplow accidentally dumped too much by the driveway and then the homeowner made things worse by over-salting the sidewalk.
Photo 3 (and a little bit in photo 2) shows a number of light tan tufts of apparently dead grass. My lawn in Wisconsin has these too; this is not a dead lawn grass but a dormant weedy grass. I've never been able to identify it, but it'll grow about 6-8" tall if not mowed and seems to spread a bit. The good news is that it'll turn green later in spring.
The area by the shed may be the result of compaction from vehicles when building the shed and/or may be the end result of covering gravel with a few inches of soil and then seeding. In either case, drainage appears to be the issue. The easiest way to check is to simply stick a shovel in the soil and see what you get when you turn it over; if you can turn it over, that is.
If I'm right about the over-salting, this grass is dead and will remain dead until spotted knotweed and prostrate spurge make their homes there. Because the area is relative small and since the soil is likely to remain contaminated until the salt leaches out, I'd dig out the top couple inches of soil, replace it with top soil, and then sod it.
To get rid of that weedy grass you can either use RoundUp, which is likely to kill any adjacent grass due to drift, or manually dig it out (that's not too difficult as it's shallow rooted). Again, you won't notice it much when it greens up, so you could just leave it.
In all of the photos (except the one with the shed), I'd probably grub out some of the larger dead areas and spot-seed, but I'd wait until May to do so.
If the area by the shed is indeed as compacted as I think, then you'll probably need to till it to break up the compaction, then smooth it and reseed it. If it's gravel, then you'll need someone with a skidsteer (try to keep it on the gravel area, not on the rest of your lawn). They'll have to skim off the gravel and replace it with topsoil, after which you'll need to smooth it and reseed.
Part of your issue is probably the grass itself. I'd bet that the grass was laid as a bluegrass only sod or a mostly bluegrass seed mix. This is inappropriate for our area of the country. Here, you'll want basically a 30/30/30 mix of fescue, perennial ryegrass, and bluegrass, especially given your shade concerns (bluegrass doesn't grow well at all in shade). Please note that all grass seed mixes must by law indicate the types and percentages of the grass in the mix. Reputable mixes indicate this on a very noticeable label; poor mixes hide the information on the bag because they have terrible seed choices. This information should be in English, not botanical Latin. Do not buy any mixes containing Annual Ryegrass or anything called Poa annuus. One note - a good seed mix for our area is called La Crosse (it was created for the athletic fields at the University of Wisconsin - La Crosse).
Finally, as noted in another answer, get a soil test (you should be able to specify that it's for a lawn), follow the instructions that come with the results for improving the soil, and mow high (3" is correct)—this helps reduce water loss and cuts down on weeds.
What's not listed in any answer is that:
You should only water during a drought, and then one inch at one time each week, at most. It is okay for an established Northern lawn to remain unwatered for up to six weeks (yes, it'll go dormant, then it'll green up again when watered by rain). How do you know you've watered an inch? Place an empty pie time weighted with a rock on the lawn and mark the time you start to water; when you get an inch in the pie tin, mark the end time. Depending on your sprinkler, that's the amount of time you'll need for each area of the lawn to get one inch of water with that sprinkler.
Use a mulching mower! The clippings feed your lawn throughout the growing season and can reduce fertilizing from the usually recommended four times a year to three times a year. This is best, however, when you have a decent lawn to mow (mulching right now will do not much in the area by your shed).
Regardless of what you do, do not seed until at least May; nothing will sprout before that unless we get a very early Spring.
A couple of thoughts occurred to me while answering a comment on a different answer.
The first picture may actually show an area that needs dethatching (thatch being defined as dead grass crowns). The solution here is to rent a dethatcher for that area.
The previous owner may have one or two dogs that hung out by the shed. This would at least partially explain the terrible lawn there. If there is no compaction or gravel, then the solution would be to grub out some of the dead areas and reseed in May.