. . . Pretty much just got everything off my computer, stuck it on the thumbdrive and stashed it . . .
Copied? or moved?
. . . In this folder is:
In which folder?
. . . I foolishly assumed when I got around to it I would open my bicoin client and it would know the path to my wallet file . . .
No. the bitcoin client expects the wallet.dat to be in a specific path. If you move it to a new path, the client won't be able to find it and instead will create a brand new wallet.dat in the path where it expected to find the old one.
. . . I didn't expect it to work but i tried opening the wallet.dat file with my client . . .
How did you do this?
I just want my bitcoin-qt to open the wallet.dat file.
Then you need to make sure you still have the correct wallet.dat and that you are putting it in the correct path on your computer.