Browsers display italic text

All browsers (latest versions of Google Chrome, Opera, Firefox and IE8) display text on certain pages as bold italic (it appears to be Arial Black Italic or Arial Bold Italic).

www.opera.com is one such page.

All fonts settings are set to defaults.

When I copy the text into an MS Word Document it comes in as Times New Roman.
I have reinstalled both Arial and Times New Roman Fonts with fonts from a machine with an identical install image that displays the pages correctly (which interestingly is not with Times New Roman).

I have reinstalled Firefox and Opera with no effect.

Does anyone have any ideas how to fix this - it is driving me crazy as many pages are very hard to read.

No other prgrams seem to be affected - only browsers - a Google Chrome grab is attached - looks like this in all browsers.

Any advice or help would be greatly appreciated!

Fixed!!! I had a lot of Helvetica fionts installed so just to make sure I deleted them all. Issue is now gone. I will reinstall the Helveticas now and see if it returns :)

Very much appreciate the assistance.

hi friends, i use office 2007 , when i was write with times new roman , italic is seem but i don t wanna italic , it is changed by itself . i must write my graduating projects with times new roman (normal) ,Do you have suggestions ? can u help me ?

I experienced the same problem.
What did cause this problem? Font: Helvetica 96 black italic (Helvetica Neue Black Italic).

Tip: delete all Helvetica fonts and look at your browser text again!