In reply to jasonC abroad:
It's worth bearing in mind that there are two very different types of cloud storage. Storage for syncing and accessibility across multiple devices (Google Drive, OneDrive, Dropbox, iCloud etc.) and then true backup storage (iDrive, Backblaze, SpiderOak etc.).
It sounds like you should be looking at the latter category, though you'll probably get some recommendations for the former anyway.
The best option really depends on how much data you need to backup and whether it's all on one computer or spread across two or more, because different services have different pricing models. It's also worth thinking about your upload and download speeds because they will control how long the initial backup takes and how long recovery would take in a worst case scenario.