Good morning Mark.
There are a few general things that can underlie a cooling problem:
A couple of things to think about?
- Are both the refrigerator and freezer having trouble, or just one of them? The refrigerator section is usually cooled by circulating air from the freezer into the fridge compartment, using a variable slide vent to manage how much or little air is passed to the fridge part. (This is why sometimes you'll have stuff in one section that seems to get frozen at times - it's sitting right next to the vent). If this vent gets stuck, especially in the closed or mostly closed position, the fridge compartment won't cool enough. the culprit is often that ice has frozen into the mechanism for the vent movement. You'll want to look up a DIY on checking that out. Here is one aimed at Kenmore/Sears/Whirlpool, but it'll no doubt overlap over 90% with your Roper.
Freezer to refrigerator vent frozen 1
There is also a site I can point you to that talks a bit more on possible culprits (with parts for sale, of course)
Roper Refrigerator Freezer is Cold But Refrigerator is Warm
If everything is warm, fridge and freezer both, then you're generally looking for either a dead/worn out / dirty thermostat, that may think the fridge is cooler than it really is, or possibly an issue with the compressor.
Also, if the freezer area is clogged with ice, this can influence the thermostat, and also impair the ability of the coolant to pull heat out of the system - (you have to flow the heat through a big layer of ice, which makes the system less efficient).
You can also look to see if you have a tribe of dust bunnies that have taken up residence on the cooling coils. If so, dust them off with a soft brush or some compressed canned air (or a vacuum cleaner wand)
Last thought - if the cooling fan for the compressor has stopped, failed, or gotten jammed, that will significantly reduce the compressor capability, and burn it out before long. Make sure the fan is spinning when the fridge is plugged in.
Hoping this helps. If you go do any defrosting, avoid doing it with sharp objects, and use some patience. One tiny pinhole in a freezer coil and you're looking at a repair that will almost certainly cost more than the fridge is worth.
Good Luck!
D