I discovered both of these places last summer and have been back for lunch several times (haven't been for dinner). I go out of my way to eat there if I'm nearby.
Glen Ellen: Olive & Vine, 14301 Arnold Drive, 707-996-9150. It's in the complex just south of town that also houses the Olive Press (well worth visiting also). Olive & Vine is a catering company that also has this storefront cafe. I've been pretty well stunned by the food each time, from the best French onion soup I've ever had to great sandwiches and much more. The menu changes often, maybe daily. But don't miss whatever soup they have.
Healdsburg: Lotus Thai Restaurant. It's on the north side of the town square right next to Bistro Ralph. It's quite narrow and used to be painted white and was easy to walk by without seeing it. Now it's painted purple and you definitely won't miss it. It's complex Thai flavors without the heat that comes with a lot of Thai food. The owner says that "hot" is regional in Thailand and her food is from other regions. I love Thai food in general and eat a lot of it. This ranks right up there with the best.
The owner has recently opened a new one, called Bangkok Thai Cuisine, in Santa Rosa (2770 Cleveland Avenue). I haven't been there yet but hope to go soon.