By far one of the best tools I have ever found is Yumi.http://www.pendrivelinux.com/yumi-multi ... b-creator/
Yumi is a multiboot loader that does it all. Grabs the iso and creates a bootable usb fob.
I highly suggest you get at least Clonezilla and some partition manager on a bootable device.
If you take like a 128G device and create a 8 gig bootable partition and a 120 gig linux partiton you can run clonezilla from the first partition and back up to the second. Works really well and considering you get fairly good compression w/ clonezilla you can backit up a good size pc.
Compression being what it is your results may vary. You can do the same on a hard drive.