Well this is my opinion, so here goes....
1st I think that for safe reliable storage I would go w/external hhd.
2nd If you are looking to reasonable fast backup & storage, go w/usb.
3rd online storage is good, but costs extra money a month.
To sum it up, I would go w/internal or extenal hhd for storage.....
Using Partition Magic or Norton Ghost, you can make a Copy of your whole hhd, & burn it to a Disk.