The way refrigerator and freezer work, they are built to be in a certain orientation and will not work when on their sides. So, I would not lay the freezer on its side.
On the other hand, a refrigertor does not need to be so cold, and it is normal for a refrigerator to have cold leave when the door is opened, as refrigerators normally are upright and with a door that opens that way.
One thing to think about is that refrigerators do not need to be as cold as you are aiming for, so the temperatures you are mentioning should be fine. I keep my refrigerator at 40'F to a few degrees lower. SO your readings are fine for use as a refrigerator.
Set the temperature for only as cold as you need it.
Fridge should be 36-40F, and the freezer should be 0-5F (-17 to -10C). Fridges set 10 degrees lower than needed (or freezers set 5 degrees lower than needed) can increase energy use by as much as 20-25%. Personally, I set my own fridge to 56° because as a vegan I never store super-perishables like meat or dairy.
To test the fridge temperature, put a thermometer in a glass of water in the center of the fridge and leave it there for 24 hours. To test the freezer temperature, put the thermometer between two frozen packages. If the temperature is colder than needed, then set the fridge to a warmer temperature.
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