Also on topic but away from dedicated software(s) to stop Ransomware, a backup solution is the key point to protecting yourself, however I'll add that prevention is better than a cure. Most AV (paid/free) & their subsequent suites would be more than enough to protect yourself from the main ransomware families, but I think with anything you do online you should use common sense when using the web.
My mantra online has always been "If it's too good to be true, it normally is.", following from this as well just have logical browsing habits, don't open up PDF, docx or other file formats from people you don't know, do not enter websites that look dodgy, out of place, spelling mistakes etc. A home user is less than likely to get a ransomware outbreak if they adopt sensible browsing habits/procedures.
As the OP did state ONLY about a dedicated Ransomware program, I would still suggest Checkmal Appcheck Anti-ransomware Free or Paid, but this alone will NOT stop a ransomware infection. In my opinion I do not think this type of software is really needed.
Just backup your data weekly or daily, update everything (PatchMyPC if needed), update/patch your OS, have a firewall and AV, adequate browser security, and in theory you should be ok from infection.
~LDogg