I see. Well, unfortunately I think the two things (borders and hexes) are mutually exclusive when it comes to Greyhawk maps. If I remember correctly, the original folio, '83 box, and From the Ashes all have hexes, as does the new maps currently being published in Dungeon magazine (which are excellent, by the way). The stuff from the Greyhawk '98 line and the Living Greyhawk Gazeteer have borders but no hexes, and the map from the D&D Gazeteer has neither.
So, moving on to other criteria, I personally like From the Ashes more than many people seem to, but I don't recommend it if you're looking for a vanilla D&D game, as it's much more dark and political. So you probably want to stick with either the early stuff (folio or '83 box) or the newer stuff (LGG or D&D Gaz). The original folio has bare sketch of details, not even including names of rules, and leaves the DM to fill in the gaps. The '83 box expands this a bit but still leaves plenty of room for th DM to do his own thing. The D&D Gazeteer is somewhere in between in detail, though closer to the folio, and is set in the current timeline. The LGG is your pick for one stop shopping with the maximum level of detail, and is also set in the current timeline.
As for adventures, really it's pretty easy to make almost any generic D&D adventure fit, though certainly there are plenty of classics to choose from. Folks seem to like the Village of Hommlet a lot as a starting adventure, and it's not too far from Greyhawk City. Dungeon is a great source of easy to use Greyhawk material, and somewhat recently (issue #114), published "The Mad God's Key", a 1st-level adventure set in the city.
Additional details about the area around the City of Greyhawk are available in the City of Greyhawk boxed set, From the Ashes, and The Adventure Begins. Also, Dungeon recently published a cool article about the neighboring city of Hardby. I'm not sure what issue it was in off the top of my head, but it was probably one that came out around this past summer or so.