I have addressed that risk as follows : I have both a new Desktop and a new laptop. Both are Windows 7. I bought a 32Gb USB stick for each, and I update modified files for each one to its own separate stick once a week. A few truly critical folders I update as soon as they change, updating the changed files only. I also make data DVDs (25c for reliable ones in bulk) at least every three months of all photo folders family and otherwise.
I should add that I keep a copy of my critical files, mortgage, payments list and passwords file in password-protected form on BOTH computers.
Been there. Don't want to repeat.
You are getting there BUT what do you do in the brief frantic moments when you smell smoke? Do you have those DVDs & USB sticks in a “Go Bag” beside your bed?
If this is your method, buy a rated safe with a reasonable fire resistance. Me, I got one that will tolerate 90 minutes of 2k F and since my house would never burn that hot or that long, I hope that no 747 nose dives on me.
Your choice of either external backups or confident in home storage resistant to home disaster. Yes, it is unlikely BUT do you feel lucky?