pay the ticket, of course. you may or may not get it put on your record or insurance. I got a ticket in Maine once (while I had an OR license), in a rental car, and it didn't go on my record in OR (or WA, when I got a license here)...but I think I got lucky. In your case, I probably wouldn't go to court because they may ask you for the reg/ins info again and then cite you for not getting a WA driver's license when you moved here (which you have 30 days to do legally).
this may help too: http://www.dol.wa.gov/driverslicense/
my best advice though is to slow down and not have to worry about tickets in the first place, especially after long days in the alpine.