Is there a lasting solution for iMac freezing?

A lot of people are having problem with freezes in Mac OS Lion and up. For me it's on an iMac 2008 that I want to let my daughter use. It can't be hardware as it worked with 10.6, as many seems to testify to.

Once again Apple abandon users. I had a graphic problem with a slow performance on a MacBook Pro as a result (many years ago). I was not alone. I've learned that when more than a few report the same issue it's normally a bug or a hardware problem. Same thing then, it worked before with 10.4 (if I remember correctly) so most probably software related. I waited for an update but it never came. This is a deja vu.

As far as I can understand there's no lasting solution for Mac OS Lion +. Correct? Crossing my fingers for being wrong.