I really like La Cachette De La Plage on Indian Rocks Beach. It's lovely inside, the French cuisine is delish, and you get to bring your wine with no corkage fee!
If you like Thai, Talay Thai in Redington Shores is really good (they have the most amazing crab soup), ambiance is nice, and it's pretty inexpensive.
I can't give info on the nostalgia part since we've only been here three years but we stopped into Guppy's last night for dinner and it was awful. We had enjoyed it the couple of other times we'd been there. One problem was sitting outside with the roar of motorcycles and a broken fan but the calamari was bland and the black grouper was flavorless as well. I also think the automatic adding of 15% to the check results in dismal service. We waited 10 minutes for a bottle of wine only to have the waitress come back and say, "What wine did you want again?" We have eaten at the Cajun Cafe the prior poster recommended and it was delicious. But my experience in general in Florida is that many restaurants are inconsistent--good one time; not so great the next.
Frieda's Cafe is a great spot for pastry, cakes etc... they do nice sandwiches and soups as well. Located in Largo, so not far from the beaches in pinellas if you take interstate 275
9700 Ulmerton Rd
Largo, FL 33771-3603
Really lovely Cajun food at Cajun Cafe on the Bayou - also close to the pinellas beaches. Speaking as a Louisiana girl this is the best Cajun / Creole food I've had in florida.
8101 Park Blvd
Pinellas Park, FL 33781-3720
Steller Indian in the roughly the same area Taste of Punjab
Taste of Punjab India Restaurant
6540 Park Blvd
Pinellas Park, FL 33781-3142
I am not a Florida, kitch, seafood person but these are all really stand up places I go to on a continuous basis and have always have wonderful food and service.