I would use Ghost 15, True Image, or EaseUS Todo (freeware). My favorite is Ghost but I use all three. First backup the system reserved partition, and then the OS partition.
I attach the HDD either with an external caddy or plug it into my ICYDock MB971SP-B (along with HotSwap! 6 -- a better freeware undocking program than Win 7 uses). Usually the HDD should be unallocated space to do the backup, and it is best to run CCleaner first to empty caches and temp files.