I often wonder what people do for all the videos they make of their kids. I do not want to lose them, but in the age of HD video, where do you store them for the long term?
An hour of 720p = ~1.15GB
An hour per week for a year is ~60GB. On a hard drive, you can fit 30 years of data at that rate into a 2TB drive. Or you could put almost a year of data onto a dual-layer Blu-Ray disc (50GB).
^I personally have a really hard time seeing quality gains in video above that.
To do offsite, in case of fire, you can clone backups onto another harddrive or every few weeks or months onto blurays and store them at a relatives, safety deposit box, or somewhere else you consider safe and accessible. Or you are willing, for offsite matters, go a cloud provided like Google, Box, DropBox, which will charge you $10-20/mo for a TB of storage on their servers, you can use that.
I personally, don't use much offsite storage, for most of my data. I make occasional Blu-Ray or thumbdrive clones of important files and keep them in my bedroom, and accessible if I have to run. And while traveling I'll bring a set of thumbdrives with me.