Random
you need to have this in draw; the lines are only ran one and not throughout.
Better is this:
x=int(random(25,450));
y=int(random(25,450));
How draw() works
another sad truth: draw() updates the screen only once at its end and not throughout.
So everything that happens in the for-loop is added up on the screen and then displayed all at once on the screen at the end of draw(). Therefore you cannot see any animation using a for-loop. Bad.
To avoid this: Destroy the for-loop, say int i=0; before setup() and use the fact that draw() in itself loops automatically: say i++; in draw().
e.g. to slow this down by 10:
if(frameCount % 10 == 0)
i++;
Remark
…and implement i<word.length() …to avoid an error of course…
Chrisir