New to 1995 Hunter 29.5, so I am wondering when to request a pump out? I noticed today that the toilet is full of water and does not drain when I pump. Guessing that I need a pump out.
Your tank may be full, but I'm betting that you also have a blocked tank vent. When air displaced by incoming waste can't get out the vent, the system becomes pressurized, creating back pressure. A blocked tank vent will also cause a pumpout to pull a vacuum that won't allow the pump to pull more than a gallon or two out. A strong pumpout pulling against blocked vent can even implode the tank.
So before doing anything else, check your tank vent...starting with the thru-hull. Use a screwdriver blade, ice pick..whatever works to clean it out. You may also have a blockage at the other end of the vent line--the tank fitting and that end of the hose. Open your deck pumpout fitting to relieve any pressure (I'd be carefull to stay downwind of the fitting) before removing the vent line from the tank. Clean out both the fitting and that end of the vent line.
There's a lot of information in the archives of the Plumbing and Sanitation forum about how to maintain a holding tank. You'll prevent a lot future problems if you'll spend some time reading some it.