If you want to do traditional row planting and tilling, you might think of covering the entire area as soon as you can get in there in the spring with black poly, and keep it there for as long as possible to let the sun kill off the grass. Then till and plant and keep up with almost daily and diligent weeding until you get the area established for vegetables.
Another method that that I prefer for raising a lot of food, and use at my at my 35X60' home garden, is to plant in raised beds. To do this build and lay out as many 4X10' boxes built with 2X10" lumber as you care to. I don't use treated lumber, and have had some of these that are still solid, and in use for well over 10 years. Under each box I simply laid out sheets of cardboard or newspaper over the grass and filled them with compost for $20 a yard loaded into my pickup from the local greenhouse. Once you get these going and mulched with leaves and additional compost now and again, you will have a very productive, till-free, well drained, earthworm rich, and virtually weed free garden. In between my boxes I mulch heavily with leaves and keep the rows wide enough for a wheelbarrow, with an even wider row down the middle for my four-wheeler and trailer. I also attach a 2X4" cap all the way around my beds for seating while working.
