It is OK to cool in the kettle if you have a good lid and starsan the lid prior to popping it on the kettle. Pitch as soon as you can get to pitching temp... don't let it sit around longer than required. In my basement, it used to take me 16 hours to go from boil to pitching temp. The nice thing about no chill is that when you put the beer into your fermenter it has had 16 hours to settle out all the break and trub.
DMS is not an issue if you have a vigorous boil. If you have a lot of pilsner malt, boil for 90 mins, but it needs to be vigorous. I never had a problem with DMS in my no-chills. It is a great way to get into brewing on the cheap and easy. I no-chilled extract and all grain brews in the kettle for well over a year before moving on to a more elaborate set-up. Good luck! N_G