My NYC geography is very shaky, so please bear with me!
Am visiting a friend who lives in the Meatpacking District; we will be shopping at Saks and, I was told, "on Madison Avenue". Could you help with some restaurant ideas for dinner in these neighborhoods? I won't have very dressy clothes, but I will have black wool pants, so won't look like a total slob; a place where one could wear (nice, not crummy) jeans w/b great, too. We don't eat meat, but seafood is OK, any ethnic cuisine is ok; warm atmosphere, a decent wine list, creative food, not stuffy, are plusses.
I hope that's not too vague! I look forward to your replies.

Well Madison Ave runs north and south for miles through Manhattan - so you would have to give us a cross street for us to pick out a neighborhood.

And very few restaurants are "dressy" in NY - if by that you mean a man wearing a suit and a woman a nice pants outfit, dress or suit. Black pants and a nice sweater count as business casual and will be fine for about 95% of the restaurants in the city.

To be of any use though - you need to give us a price point.

If your friend lives here, why are you looking for restaurants? Morrell's is a wine bar with good food at Rockefeller Center which is right across from Saks. http://www.morrellwinebar.com/

Caviar Russe http://www.caviarrusserestaurant.com/gallery is a small hidden gem up a flight of stairs in a small building on Madison & 54 st. (near Saks) that serves very good seafood and sushi but it can be a bit pricey. There are not a lot of restaurants on Madison Ave. since real estate is so expensive but if you head a few blocks east you'll do better. The shopping on Madison ave. is mostly very pricey. Is that the kind of shopping you plan?

Fishtail is a good, inventive restaurant near Bloomingdales. http://www.fishtaildb.com/

PS, in Manhattan, when you say "downtown" it means literally that, the area at the southern end of the island. Midtown is where Saks and Rockefeller Center are located.

Assuming you mean near Saks, I'd like to suggest Pampano, on 49th between 2nd and 3rd.

http://www.richardsandoval.com/pampano/index.htm

It's modern Mexican, the sort you might find in a good restaurant in Mexico City, with an emphasis on seafood. Been there several times and never disappointed.

Yes, but "shopping on Madison Avenue" basically means uptown (on the east side) and is definitely upscale. As others have said, not a lot of options up there. This is "ladies who lunch" territory - even if you head east to where the frequency of restaurants is greater, IMO the selection isn't great. (There was a thread recently from someone staying a bit farther uptown in the east 80's - a lot of restaurant rec's on there if you can find it.) Also, there is a block in the east 50's with a number of Indian restaurants on it - always a good "veg" option! If you're interested, I'll try to remember which one it is exactly...

The Meatpacking is very hot these days, with lots of high-end designers and high-end hotels/eateries. Everyone is in "casual" attire (except for clubbing) but I always feel outdated and frumpy there like I do nowhere else in the city LOL. A lower profile restaurant I like in the area is Fatty Crab. It's tiny and very popular, so try to get there either early or late!

Check out menupages.com; it's a great resource for NYC restaurants. You can look by neighborhood, cuisine, etc. and get lists of names you can scan through to see what appeals. Restaurant details include sample menus so you can decide if it's really what you want...

Thanks very much for these ideas! Noted.

Let's try this again: friend lives downtown, we will be shopping at, yes, pricy ,boutiques along Madison Avenue, uptown. I assume these are near Saks, but am not sure. (Btw, the shopping is for her, not for me; not that it's relevant.) Yes, friend does live in Manhattan, but she doesn't dine out there very often; also, I'm a bit more interested in good food than she is. So I thought it would be nice to have an idea or a reservation or two in hand and not rely on her to do all the planning. Lunch will be grabbed on the go between appointments, so one or two dinners are really my goal.

Sorry, forgot about price point. How to say this? Per Se is out of the question, but the middle-high range, or lower, of course, w/b fine.
Thank you again for the ideas!

IMO, Meatpacking is tough dinner-wise because it is so trendy, but you could look into any of the big name restaurants there (The Standard, Pastis, Spice Market...). As I mentioned above, do take a look at Fatty Crab and see if it interests you!

Farther south, I like Surya for Indian: it's not fancy, but a step above the "usual" Indian restaurants in NYC. Across town, recently I had a lovely dinner at Travertine on the Lower East Side. They had some yummy non-meat options on the menu.

[The stretch of Madison Ave with the shops starts about 57th St and goes easily to 79th St if not above. Saks is at 50th Street, and 5th Ave is one block west of Mad.]

From the Meatpacking District , you can find lots of wonderful dining options..From Meatpacking you can walk to all of the following:Vietnamese, Omai on 9th Ave, Indian, Bombay Talkie on 9th,both in Chelsea, Spice Market in the Meatpacking dist,Fatty Crab on Hudson St in W. Village, Cookshop on 10th Ave, Chelsea, Standard Grill,Washington at W.13th, under The Highline,Red Cat, 10th Ave, Chelsea..