Drive your car. They will give you a parking pass good for 3 or 4 hours. The GF is a monorail resort. We did this when doing breakfast at Chef Mickeys.....hopped on the monorail and took a ride over to the MK (not going into the MK) then took a boat over to the Polynesian and spent a little time just looking around the resort and shopping in the gift shop. Then we hopped back on the monorail back to the Contemporary to retrieve our car. Was a nice little lazy day outing (our breakfast was late morning so the monorail and boats were not crowded at all)......it was very relaxing.
Except that the parking at CR and the parking at GF are two totally different beasts. AND if you leave your car beyond the three hours, you may be in for an unpleasant surprise.
The self-parking at GF is not remotely convenient to the resort. It's not at ALL like the parking at CR, which is closer to the park than the CR itself. There's also no way to walk from MK to the GF parking lot. It's one of the downsides of GF. Depending on where you park, and how long it takes to get a crossing signal at the traffic light, it can eaily take a good ten minutes to walk from the lot to the front door of GF.
If however, you are staying at WL, most buses are shared between resorts -
double check with your bus driver before you board - but just about any park bus will take you directly to GF. (I think there's a few dedicated buses during peak hours that only stop at one resort.) From WL, your best bet for getting
TO GF quickly by far would be to take the bus! (going directly back to your WL after eating though would have to involve going to a park first, probably MK would be fastest.)
It also depends slightly where you are eating at GF. I'm guessing you mean 1900PF, since the only other character meal there is the Princess Tea Party. Your restaurant is located onthe first floor near the front door.
If your home resort is on the monorail line, then you'd take that. Otherwise, you'll probably need to take your resort bus to MK first. From the MK bus depot, you'd have two options for getting to GF - the resort monorail (GF will be the fourth stop) or taking the boat. Since the boat goes directly to GF, it's probably your best option.
So that said, driving may still be the fastest option - depending on what you decide to do after the meal. Driving around WDW can be a bit confusing though, so it kind of depends where you interests lie. As long as MK is open, taking DIsney transport may be the more relaxig option. After MK closes however, driving is the far better option.
