I had a similar problem recently and was given advice by the AB gang. Bit different to your problem in that freezer was over-cold and fridge was like a toaster. Defrosted for 36 hours while shopping around for new ff/thermostat, left it alone for another day, talked to it nicely, took back all the names I called it and switched on again.......and, touch wood, it's working fine! Worth a try. Really really defrost to give the best chance. If you do need to replace, have a look at Which reports (you can sign up for a £1 trial which will make reports available online). I seem to remember that Samsung and Indesit came as best buys in the £300ish range).