It's a shame what folks will do sometimes...at any rate, to determine if you have a serious problem with the unit, a technician might first have a look in the freezer section where the cooling coils are located. Since you maintain that the temps on the fresh food side are high, yet the freezer seems semi-normal, one might suspect 2 possible causes.
1. Defrost problem (coils covered in thick frost)
2. Sealed system problem (poor or partial frost pattern on coil)
The first one is simple to resolve in most cases, but a sealed system issue means expensive repair work and is beyond the value of this model. If you can get to the evaporator coil in the freezer and look at it yourself, you might report back the findings.
Also be sure the unit has a cover on the back where the compressor is, or it can cause the unit to run warm.