The process took almost 24 hours, during which the lying software kept telling me I had "35 minutes" left in the process. Finally, the screen said I had successfully cloned both partitions.

I switched the old hard drive for the cloned one. The Thinkpad couldn't see the drive at all and suggested cable problems. Swell.

I switched them back again, putting the old drive back in and the new drive on the adapter. The computer booted just fine, and showed me my old C and D drive, and the two new partitions as "E" and "G" ("F" is reserved for my CD drive). The data was apparently all there.

Okay, fun time. I put the new drive back in the computer, and went out to get my Microsoft CD to boot it from that and see what I could do. Started it up to put the CD in, and lo and behold it started normally as though nothing had ever been wrong.

I have no idea how I fixed it, but I'm glad I did. Seems to run fine now, and I have a lot more elbowroom for data. I also have a nice gadget for using spare hard drives as clone backups of my boot drive.