I wouldn't worry too much about missing the hotel entrance. As you exit the I-4 onto the Osceola Parkway, you can't miss the hotel and the entrance will be on your right-hand side, so just stay in the inside lane. Even if you should miss the entrance off the Osceola Parkway, you just need to hang a right at the lights onto South International Drive and use the main entrance.
We've eaten at all three restaurants. Old Hickory Steakhouse is one of our favourite restaurants in the area, but it is quite pricey. It's set in the Everglades section of the hotel and is styled as a swamp hut on stilts complete with alligator-infested waters! Inside it's divided into intimate nooks and crannies. It's rustic, yet very atmospheric. If you want to eat there, I'd suggest making a reservation in advance as this is a convention hotel and, even when the rest of Orlando appears relatively quiet, it can be difficult to get a table as a walk up.
Sunset Sam's Fish Camp is at the opposite end of the hotel in the Key West area. Part of the restaurant is set aboard a yacht on the marina (all under the glass atrium). Unsurprisingly, this is a fish restaurant. We've only eaten there once and, whilst we enjoyed it, the fact that we've never been back probably suggests that we weren't blown away.
Villa de Flora is a buffet restaurant serving breakfast, lunch and dinner. It's in the St Augustine area in the middle of the hotel. I'm not a huge fan of buffets, but this one does it well and, again, the theming is excellent. We've had lunch there a couple of times.