Ive been to that place where Matteos was in Hewlett and found it pretty good. Other than that, the 5 Towns is history .I did hear about that new Asian place called Midori in Hewlett, but I havn't been there. I heard it was pretty good and really beautiful.
Rockville Centre has Da Ugo's and that pretty good but very expensive and hard to get in on weekends.
Lynbrook has a tiny place called Branzino, where Villa Borghese used to be.
I was there twice and found it to be pretty good but extremely expensive, and if you order from the waiters specials, they really do a job on you.
Valley Stream has nothing I would recommend at all.
Oceanside has La Parma which is one of the best family-style Italian restaurant in Long Island. It's kind of like Don Pepe's
Rockville Centre has one good one called Dodici, I would pass on Dario's. Blue Moon has great Pizza if you want that.