How did "one" get changed to "Half-two"?

Just recently something has happened to change things like "one" to "Half-Two"; "there" to "Thor"; "mathematics" to "spelling"; and "Yours" to "Y'all's" or "you're" to "Y'all're". This happens on IE and Firefox and even happens the URL when I attempt to go to a mathematics website. The only thing I have done that I can think of that might possibly be involved is I downloaded jsMath v3.6 (Tex fonts) but I removed that and the problem is still there. Any help would be appreciated.

Try a system restore to a point before you first installed jsMath v3.6. Details of how to do this are in this tutorial if you need help to do the restore:- System Restore

How would a font change "there" (five characters) to "Thor" (four characters)?

Yeah guys, this isn't a font issue. This is some type of auto-correction or shortcut typing feature. Most likely something the user has installed and doesn't remember.

It sounds like one of the joke translator web sites that translate pages to "redneck" or "hacker" or whatever, though one of those shouldn't affect both browsers. Grumpy, is it ONLY in Firefox and IE or also in other apps?

Tried post #3 yet?

Thanks to all of you for the help. I had my daughter go to the web site that I knew always gave a problem and she got the same results. Today I checked and it's much worse than yesterday. Quatrix got it right - it's some redneck hacker with a warped sense of humor. Check out xkcd • Index page - a little down the page there is something about mathematics, and it should say 'For the discussion of mathematics. Duh.' Instead it says 'For the difcufsion o' spelling. Duh.'
Postscript - Check out the URL. What I put in there was ...forums(dot)xkcd(dot)com - so how did that get changed?