Shabbat Take-Out in J'salem
If you want to be amazed...do not miss Marvad Haksamim on King George, as chai18 suggested. On Fridays, their restaurant gets turned into a buffet take out with a HUGE selection of items (you won't believe it until you see it), some a la carte, some by weight, nothing expensive at all, particularly compared to US take out food prices. Last time, we bought a stuffed onion filled with meat for about 6 or 8 shekel- it was not weighed, sold by the piece. It did not make it to Shabbos dinner- OMG yum. They also sell salads, challah, desserts for one stop shopping, but your main focus should be on the prepared hot food. Couscouses up the wazoo, meat, umpteen chicken varieties, veggies...you will be amazed and you will enjoy Shabbos immensely.
marvad haksamim on king george in the basement of the sochnut building
heimishe essen on KKL but there stuff is pretty gross or i guess heimishe :)
theres another take out place also on KKL near heimishe essen that just opened dont think it has a name yet but ur standard israeli mizrachi shabbos take out
go to any of the places in the shuk
la guta on beit lechem has some fancy stuff and prices arent that crazy