Help!

Two months ago I purchased a new Toshiba laptop with windows basic 7. I was using explorer and sometimes when that went down, I would switch to Firefox. Well after a month, explorer would no longer work. No idea why ... it just would not load.

Ok ... I'll just use firefox. Everything was going fine until a few days ago when I was sending an email to a friend. All of a sudden, the font size changed from comfortably readable to Christ I need a magnifying glass. I have searched the web, looked at my computer settings and cannot find anywhere to change font size. My webpages that appear upon surfing are fine. It is just the emails. Pisses me off, because the email takes up 1/4 of the page and the rest is blank i.e. available for larger text. So, can any of you guys help me out? How do I change the font size for my emails in Windows 7 basic?

cheers