Mint, mate
I switched from Fedora to Mint 17 LTS 6 months ago for stability reasons, and I can recommend it to anyone. Being a business user, and over the age of 12, I went for MATE, and I have to say it is a great working environment. Reliable, logical, configurable. It does a great job and then gets out of the way. There isn't really much to say about it and that is one of the features of a good windowing environment IMO.
NB My hardware is not old. Quad core i7, if you please. The combination of a fast CPU and fast, minimal desktop is doubly wonderful. The desktop never pauses for anything, ever, not even for a second, even with the encrypted /home. (except for scanning wireless APs).
Anyway I heartily recommend Linux Mint 17. Tip: Replace LibreOffice with OpenOffice for better stability.
Biting the hand that feeds IT
