I've switched to Linux for a few weeks now, running Linux Mint Cinnamon 18 LTS on a Am1 Athlon 5350, this seems to be working fine, didn't hit any big bumps, installing was totally painless and after some poking around I've been able to find everything you'll need for a web browsing, mail reading, video streaming desktop machine.
Thought I'd make a post about what I've found out so far.
Browsing: Easy peasy, its Firefox as standard browser, you can add others like Chromium or whatever you like, heck you could even use (e)Links for text browsing.
E-mail: Thunderbird, of course there are heaps of others on Linux which can/will suit about any need.
Sound and video, there's the standard stuff like VLC player, Video player for music and video's, Brasero for DVD/CD burning and I've added Audacity for converting and editing soundfiles.
Office: Libre Office with all the bells and whistles should be able to do any document task, personally I've used Abiword a lot in the past so I've added that one and for the simple stuff there's the standard text editor but I prefer Leafpad, I also use Jpilot because I have used Palm software for ages and Jpilot can use its ancient data base, I've always been too lazy to convert it to something more modern.
Graphics: standard install includes Image viewer which does just that, Gimp image editor which is good but utterly confusing so I've looked around and found a simpler but, for me, adequate image editor called Pinta.
Other useful stuff include a tool called Disks, it will show you information about your harddrive like partition info and also SMART info so you can keep an eye on your HDD/SDD to see if its not going to explode in your face anytime soon.
Psensor, its a tool for keeping track of fan speeds and temperatures of your hardware.
So what I've got is a rather nice working desktop machine, with the hardware it has it won't do any gaming though but for everything else it will suffice.
I'm not entirely Windows free yet, I have one game rig with Windows 8.1 but it only contains windows and Steam and that is all.