Personally I wouldn't walk around 'meeting' people everybody will hate you. They just want to eat their meal not coo over your dc.
I think you need to expect to do some amusing but also they do need to learn to amuse themselves. Also if your table ends up looking like a creche you're not teaching them much about having to be in situations when it's not non stop amusement.
We used to take a couple of boxes each of raisins(yog coated ones for a treat) to nibble whilst waiting for food I'd only take 1 or 2 very small items to play with otherwise they'll just want loads of stuff to appear out of your bag. If they know you'll only ever be bringing a book and mini pot of playdough they won't whine for more.
Mine all had these mini etch a sketch type things from ELC. We got hours of amusement from those eg draw me a face,what number is that etc. Mine always adored books so I simply took a few books and read to them. A new comic is good too or a mini pot of playdough(eg make a snake etc) Choose a table by the window so you can play eye spy or they can watch life going by.
Mine are now 5,5 and 4 and recently I took these little sticker sheets. I was a zoo,1 was a river and 1 a princess. They had to stick the stickers in the right place. DD had some left so I drew her on a napkin and she spent hours sticking bows on her hair etc. Dtwin 1 spent ages looking out of the window and dtwin 2 spent ages making his own dot to tot eg he did loads of dots and connected them(you could do that)
It's sooooo much easier now(mine are they even just sit and chat for the odd couple of minutes
This summer I'm going to take dot to dot and sticker books(if I can find tiny ones,I hate the table being covered in crap) and encourage them to chat more,read the menu etc. That's the plan I'm aware that probably won't happen
The thing is even if it's a nightmare they're still learning,we've had countless nightmare meals out but they've slowly learnt what is expected. They're not perfect by any means but I do think they now know they need to keep on their bottoms and try to speak quietly(doesn't always happen)etc.
Goodluck