Windows ME Startup Problems

I have a laptop computer running Windows Me. I started the computer with no problems but the power was not plugged in and it was running on just battery power. The battery ran down and the machine (I think) went into hibernation. After plugging the power cbl back in, I restarted and came up with the following:

Invalid sytem disk
Replace the disk, and then press any key

I tried starting in safe mode and still no matter what the same message comes up. I inserted a boot disk and I am able to view contents of drive c:\

How can I get windows to start from Dos Mode?

I did try to start in Safe Mode but it still needs the boot disk.

I have a lot of personal pictures and a few documents that I'd like to backup and then I have no issue with re-formatting and re-installing windows....but would like to easily get my files off and on to my backup external HD without loading hundreds of pictures individually onto a floopy disk thru DOS Mode (it would take days I'm sure)

HELP ME PLEASE!!!!