My questions boils down to this. If I do "dd if=/dev/sda of=usbdrive" can anybody confirm that this will get everything including mbr/partition information/all four partitions and create a drive that I can swap with the failing internal drive without losing anything? If this is done while the computer is running will it still copy everything? At this point I'm afraid to shutdown the computer for fear of it never starting again.

Secondly, how tolerant is dd of failing drives? Has anybody used it to recover a half dead drive before that can share any potential pitfalls? Did it get the data ok or is this going to be a hope for the best kind of situation?

And lastly, If the usbdrive is larger than the failing internal drive I'll still be able to expand the partitions later so I'm not losing space? this last part seems silly to ask but with my current streak of bad luck I'll end up overwriting some magic bit and forever turning a 640gb hdd into a 500gb hdd.

Also if anybody has a better solution to create a complete clone that gets everything I'm all for hearing about it.

PostScript: I had been making periodic backups however when whatever miasma that killed the laptop struck it also got the NAS :(

Post PostScript: both devices were on a UPS system.