I don't think a single time to 80 degrees is going to destroy the wine but it certainly isnt good. We live in Co Co County and it gets hotter here than there so we bought a rather large cooler and keep it in the garage. I keep it set for the mid or high 50's. That one has mostly Reds. In the house we have a smaller one for the whites and Champaign. That one is set as low as it can go mostly for the champaign. It is actually a little to cold for some of the whites but it is easier to warm them up than cool them down.
+1 .. Yup. Think caves for slow red nurturing, but honestly the way some reds are 'churned' out, they are about good to go off the shelf.
Rarely do I come across a red that needs to be set down for aging, but does need not to stay
for any length of time above 60's or it'll have problems.
As for keeping correctly, low 60's seem to work for me, and that temp can be cooler but much below like below 40's destroys the taste IMO..... And do allow some moisture to the corks like a bit of water in there or you'll dry them out = bad taste....had an outdoor/cellar and managed to find that out the hard way.
Whites, like said, I like cool, and especially the sweet ones on a hot day like a GT or Rhine type. Dry are great that way too.
Your cooler/fridge should be just fine. The only time I had wine coolers were for the cases of Champagne needed with last g-friend, and they never seemed to keep cold for some reason