I did a little bit of research before making this thread. Apparently when you try to open an ODT and get nothing but pound symbols, you're essentially S.O.L.
If I'm wrong about that, please let me know.
I thought I'd share my experience to hopefully help someone else avoid the same mistake I made -- and maybe get an answer about how to fix it. My hopes aren't particularly high for the latter.

So, here's what I did:
Backed up a folder (created in Win 7) called something like "[CURRENT] work documents"
I have a ton of other files on this drive -- everything seemed to have been backed up correctly, other than the documents in folders with [] symbols in them. I have tried renaming the folders to no avail. Nothing seems to "bring back" the .ODT documents I had in those folders specifically. For the record, all of the .txt documents in those folders appear to be "empty" as well.
Interestingly, these files all appear to have the correct size, e.g. 57kb, etc.
Hope that makes sense.
Tl;DR - Don't use []'s in your folder paths.
If there's any information that could potentially help me retrieve my files... sweet baby jesus I will give you the biggest internet-hug ever.
Thoughts?