You'll want to plan your trip in days. Don't even try to drive during the 7-10AM and 3-6PM commutes. The freeways stop, literally. South of Seattle isn't as bad as north.
Seattle: You can park at Pike place, buy something inside and get your parking ticket validated (just ask!) that way you don't have to head back out after an hour and pump the meter full again. From Pike place it's a short walk to the Piers - DEFINITELY recommend
Ye Olde Curiosity shope and there's a bunch to see and do down there including the
aquarium which is a few blocks down and pretty awesome. It's also very safe during the day. The underground city isn't too far either.
For a trip to Vancouver - start getting your passport now, they take 30-90 days. You'll want to leave seattle early and hit the border before it gets busy.
Here's the webpage there's a reason it has all those traffic flow cameras.
As far as easy... I've only been held up when moving chins/cages back and forth but never more than 45 minutes. I always get there when they open at 7AM, they are open until Midnight. It'll be fast if you don't take any fruit or critters.
On the way up to Canada you can do a day in Anacortes, it is a beautiful little town and the inter-island ferry terminal is there. It is extremely expensive to drive on but you can park at the terminal for a day and walk on and island hop and watch for sea critters. It hits Lopez, San Juan and Orcas islands. All of the islands have amazing things to see and do. You can also take a ferry to Sidney, BC (on Vancouver Island) from the same terminal. I have never taken the route so don't know what it involves.
Here's the schedule/fees
From Anacortes to Vancouver is about 80 miles.
There are so many things to see and do in both eastern and western WA, they have a ton of state parks and it's a pretty happening place. Only downside is planning around the traffic.
Have fun!
