How can I fix my Hoover fridge? (Freezer below is fine)?

My Hoover fridge is too cold! Ice forms on the rear wall, and friut and veg get ice crystals on them and are spoiled. I've put the temperature control to 1 (i.e. next to the "off" position) but it's still way too cold. I've had a look at the circuit board that is held in the slot just above the fridge, but can't see anything obviously wrong. I'm guessing that the thermostat may be faulty. Is that the case? In which case my guess is that it would be easy to replace. Is that so? It's tall (about 2.0 metres) and I've photographed the circuit board etc, in case that can help in any way. There's a sticker on the circuit board with the following information on it: ITW ISPRACONTROLS, LOT 30159-a t, DATE 0603, R3/0 +55 C, CU123001, 91201739, 220/240v 50/60Hz. Any help / advice would be most gratefully received and very much appreciated. Thanks, Rob.