I'd have thought an external HDD would be the way to go to store such backup rather than DVD's. Then it's all compact in one location. I use 1 & 2 TB external drives, but the ones below 1 TB in size are quite cheap nowadays. As the newer larger external drives go up in size, the smaller ones go down in price.

Some of these external HDD's come with their own backup software. I've no idea how good they are though.

Apple uses a system/program called Time Machine that comes with the system. In some ways similar to Windows restore backup system I guess, but is an actual backup program for external backup devices. Time Machine works well except when you have multiple accounts on the computer, then permissions get complicated (& problematic.)