I usually wash yeast before pitching rather than after harvesting. I also use filtered tap water rather than boiled and cooled (after all it's not going to be stored after washing). This seems to be what you are doing.
For a new batch I use a pint of slurry (about a quarter of the cake from the previous brew - you are over pitching if you use more).
It usually takes me about 2 hours from start to finish. I do it while I am brewing.
1) I put the pint of slurry in a 4 pint jar/container and fill with water and swirl. Let sit on the counter (it might go quicker in a fridge - I don't know).
2) After about 15 to 20 minutes there is a definate settling of the trub. When I think it is ready, I pour the liquid into another container until trub material starts to come out.
3) I top up the slurry container with more water, swirl, and let sit again and repeat.
After repeating 2 or 3 times, I end up with about 4 pints of 'yeast-water'. I just straight pitch this into my cooled wort.
If you are doing all-grain and don't have the capacity for an extra half gallon of liquid, you can place this in a fridge and let settle, pour off the liquid and pitch the yeast. The timing will be dependent on the floccculation of the yeast. Last time I tried it with PacMan it took several days to get it mostly settled.
As for the question on the kraeusen. Just rack from below it and let it settle into the cake. Swirl everything up and pour into whatever you are collecting it in.
I would normally say that if there is still kraeusen you are probably racking too early, but it is your beer and it will still turn out fine. Without the cake and kraeusen, you might find the beer may have some off flavors 'green'. If you have them, they will eventually clear up ...... just would be quicker if you left it with the yeast.