You're certainly on the right track with Tiny Core. But it still depends on the software you want to use.
With only 112MB(?) RAM, forget about modern bloated web browsers like Firefox. Maybe Fifth suits your needs ( fifth.tcz is available from the repo) but TBH, I don't know if your RAM is sufficient. Maybe Dillo is enough? (dillo.tcz) It's quite basic though.
Not sure if lightweight word processing software is currently available, but that could change if you build it or someone does it for you.
However, even though Tiny Core is a good start point for a limited system like yours, I'd try to get some more RAM.