There is another place you can check out
Click Start>Control Panel>Internet Options
On the window that opens there are 4 buttons in a line Click the
"Accessibility" button on the right
On the next window
all the boxes should be unticked. If not do this, and press Ok to save and leave this window return to
the Internet Options page.Now click on the
Advanced Tab. At the very top of this long menu check if
both boxes in the
"Accessibility" section are unticked?
If you have to change this press the Apply then the OK buttons to save and exit this program. Otherwise close normally.
I'd use Cswchan's method as a rule but if any settings such as I have mentioned above are ticked , then I think some pages text sizes could be all sorts of sizes

PS Hiya Mike B. Nice to see you answering again

Mike L.