Here is a way of doing backup which will work well for most people:
Buy a USB flash drive and copy your data to that about once every month.
For some documents and pictures a 4 or 8 GB drive should do it. If you also want to backup some movies you should go for a USB harddrive.
Ease of use
Easy but requires some manual work. You don't have to set up any accounts, automatic schedules or technical stuff. Instead you have to do the work yourself and some people don't want to bother doing that.
You might want to use an online solution - wait for another posting about that.
Better than nothing. This solution will protect you against a crashed harddrive and damaged or deleted files. If you store the drive in another house (e.g. at a friends place) you will also be protected against theft, fire and other kinds of local natural disasters. Big scale disasters such as earth quake or massive fires requires that the drive is much further away. Consider an online solution or a "NAS friendship" - see upcomming posts for that.