OK, please don't take this wrong, because this might come across harsh. But trust me, it's tough love, brother!
This, as you've pointed out, is your first beer. You're getting advice from experienced brewers, and dismissing it awfully fast. Stop doing that!
Yes, your beer fermented warm, and the primary phase of fermentation (the process by which the yeast converts sugars into alcohols) happened pretty fast. But that also means that the yeast were stressed and threw a lot of extra byproducts, which is exactly why you want to leave that beer on that yeast cake a little longer - to allow the yeast to clean up after themselves. This is the conditioning phase of fermentation, and your beer will be better if you allow it time for that phase to happen.
As for your other question about what temperature to ferment at - that depends entirely on what strain of yeast you're using. I'm not sure about cooper's yeast, but most other yeast manufacturers print on their labels the ideal temperature ranges for the strain of yeast. Usually, if you ferment on the low end of the range you'll get a cleaner (no off-flavors) fermentation, while on the higher end you'll start to get some esters (different yeast throw different esters - some fruity, some clovey, some funky). In general, you want to keep a fermenter at that target temperature - if all you can control are the ambient temperatures, then you want to keep the ambient temps 5-10 degrees lower than the desired fermentation temp, since the fermentation will be 5-10 degrees warmer than the ambient temp around the fermenter.
Generally speaking, ale yeasts are happy in the low to mid 60's (though some go considerably warmer and a rare few a little lower) and lager yeasts are happy in the low 50's.