I was going to suggest that. Wordpad probably does 99% of what ordinary people want to do anyways. Also, I haven't tried it, but I think it should be possible to work in Google Docs and save it as a rich text document?!?!? Can anyone confirm?
Google Docs spies on what you write for advertising so I wouldn't want anyone to use it.
Just get OpenOffice. Whether you want the current Apache OO or the old Oracle OpenOffice suite (up to 3.3) is up to you, personally I'm running the old one.
WordPad is good for generic things and simple stuff.
Try Abiword. This application runs on pentium 1. I believe it will run on your machine as well. This is compatible with all Office format saving it as .doc.
You could also try Jarte's word processor. It's based on Wordpad, but transforms it into a modern, tabbed, point-and-click word processor. In one mode, you don't even have to click; just point, and the function will execute automatically.
It's extremely good on XP; I've been using it for quite some time. Takes a wee bit of getting used to, but once you do, you'll wonder why you didn't make the switch sooner
There's also a free version of Ashampoo Office (same as SoftMaker). It compatible with docx and xlsx formats, and even has a PDF creator. I use it with Windows 8