Microsoft Word saving issues - taking up too much space on my HBO

I'm running Windows 7. I exported a document from one of my programs as an .rtf file, and it was huge—about 300 MB. To save some space, I saved it as a .doc instead, which brought it down to a much more reasonable 28 MB. However, there's a major issue: every single time I hit Ctrl+S, it seems like the system starts generating massive temporary files. This little habit of mine has already eaten up about 5 or 6 GB of my hard drive space, and since this is my primary work machine, every gigabyte counts...
It’s definitely tied to this specific process, because I’ve tested it a few times with smaller .doc files, and every time I save, my available disk space just shrinks a little more.
I tried running CleanMyMac and manually checking out these two folders, but nothing worked at all.

Paths:

Here is what my disk looks like now:



Does anyone know how I can clear out this junk? I really don't want to go through the hassle of reinstalling Windows because, honestly, I have no idea how to do that...

I tried running Disk Cleanup, and the tool claimed it was going to clear out about 2.4 GB once I checked all the boxes, but after it finished, my drive space only increased by maybe 400 MB. I'm wondering if the rest of those files aren't showing up as free space immediately, or if the process just failed to actually delete them... I could really use some advice on how to actually get rid of these extra gigabytes hanging around...

So, you're basically generating an .rtf file, opening it up in Microsoft Word, and then just saving it as a .doc?
And what actually happens to the original .rtf, though? Are you just deleting it entirely?

I'm going to delete it. I’ll be switching everything over to Microsoft Word just to save some space, since .rtf files end up taking up way more room than they should.

Technically speaking, an RTF file should be smaller than a DOC file, so maybe try running CleanMyMac to clear out all that junk first.

I’ve honestly never come across a situation where an .rtf file actually ended up being smaller than a .doc... I already laid out everything I did above.
This probably has something to do with what happens when I hit "save" on my Microsoft document.