Hi. Welcome to a great adventure!

You'll find that people in this area are friendly and helpful.
First: as a Microsoft employee, you have a
Microsoft Human Resources person called a
relocation advisor who will assist you in answering questions, finding neighborhoods to live in, and many other details of moving to the U.S. Be sure to ask your H.R. contact at MS who that person is, and how to contact that person. Let that person earn their salary by helping you.
Second: to answer an implied question of yours,
a "condo" is one unit in a multi-family building. A condo is almost always a single storey, with no upstairs or downstairs area, like the usual flat. Condo buildings often look like apartment buildings, and might have two units or 15 units or any number of units (like flats); it varies with the builder and the local government's building codes. So a condo is
not a detached house.
A "townhouse" is also one unit in a multi-family building, but has an upstairs and a downstairs.
So a condo is just one level; a townhouse has interior stairs and has two (rarely three) levels.
Third:
Where to live. Working at Microsoft and having children, you would probably be best advised to start by living
near Microsoft. Commuting around here can be very difficult because there are too many people moving here and not enough roads to hold all their cars. So, a sensible and comfortable idea is to live near where you work.
That means
"the east side" -- of Lake Washington. Therefore,
Redmond, Bellevue, Kirkland, Issaquah, maybe Sammamish or Woodinville.
The
Microsoft Connector Bus is a great service: you could live within walking distance from the Connector, or you could drive to a pick-up location, park the car, then take the Connector to the office. Here is the most current map of the Connector. Click anywhere on the map to enlarge it. MS keeps expanding the routes, so you can expect increased service.
Map: Microsoft's expanded 'Connector' system
That map can help you see where the cities are surrounding MS (the ones I mentioned above; opening a large map will help you see them).
The following sites will help you find rentals.
This is the combined classifieds of the two leading newspapers in the area.
In the little map, click on Eastside and Eastside Plateau. That will show you where places are. If you continue to click on locations, the map will drill down to smaller areas.
NWapartments: Seattle apartment rentals, house rental listings, rental classifieds and other property rentals in Seattle, Tacoma, Bellevue and other Washington areas, cities and neighborhoods
There's also craigslist. Be absolutely certain you DO NOT send any money to anyone until you verify 1) the person exists; 2) the property exists exactly as advertised; and 3) the person is legally authorized to rent the property. Ask your MS relocation specialist to verify any craigslist listing you might be interested in:
craigslist: seattle-tacoma classifieds for jobs, apartments, personals, for sale, services, community, and events
There are also: rent.com, forrent.com, apartments.com
For rentals: The east side has many, many condos. Quite a few townhomes. Some apartment buildings. And some houses.
To get an idea of
the local job market and volunteer possibilities, this might be useful for you, the combined classifieds for jobs of the two leading newspapers:
Seattle area jobs, employment advice and information | NWjobs
I hope this is a good start in your research. Have fun planning!
