You should never have important information on a windows machine. If you can't afford 2 computers (because only total isolation is safe) you can just get constant backups on your usb pendrive of any sensible data, so if some fucker encrypts your computer you just have to format it and they will get nothing out of it. Also install malwarebytes anti ramsonware software.
Most people use Windows; OSX and Linux are the minority, it would be helpful to list ways to secure Windows best as possible. I will start the discussion if you are using Windows. If you are using Windows 7 the best advice I can give you is not to update to Windows 10. Stick with Windows 7 for improved privacy.
1) Use Firefox, not Windows Explorer or Chrome. Go to Tools > Addons > Plugins and disable Shockwave Flash to prevent malware delivered by Flash banners. At the minimum use uBlock Origin extension to block all other ad banners.
2) Use a top rated security suite like Kaspersky Total Protection. Even with Kaspersky use good hygiene. Never click on links or banners in emails or heaven forbid open an attachment. Even friends can pass on a virus or trojan by forwarding a bad email. Most malware is delivered by email, not websites.
3) If you have more than a few bitcoin use a hardware wallet like Trezor.
4) Make a system restore disc and store safely in case you have to reformat your hard disk and restore from a backup. Get a 2-5 TH backup drive so you have plenty of space for multiple backups and backup weekly.
I upgraded my windows 2 months ago and after using it 10 day I reinstalled lap top completely and return it to fabric settings. And I stayed there cause to much bed things with windows 10 happened to me.
I like you other advices, I also use firefox, have nice security, anti virus and anti malware . I don't have so much coins, but bigger part is in Trezor.. and I have several online wallets that I use for gambling and everyday transactions.
If something like this happened to me, I wouldn't pay ransom and that is my advice for OP. You have your files that is important, now start again but with better security. There is nothing else what you can do except to be more careful in the future and not let same thing happen again.
Of course paying ransom will give more power to this little criminals. They will try to do It again, so don't give them that feeling. Cut them in root`s.