Is there any way to use a spell checker in these forums?
The right-most tool of the toolbar you see when you write a post should be a check mark with the letters "ABC". This is spell checker functionality provided through a product named ieSpell (an Internet Explorer add-on that needs to be installed at first usage).
But, when I paste things in from elsewhere, the font size changes
The discussion forums "try" to keep as much of the source formatting as possible - but don't always do it in the smartest way... Behind the scene it's all HTML code and sometimes it interprets and adapts it not exactly like one would like. Two ways around this are to use the "Paste from Word" option (third tool from the right) which handles formatting slightly differently, and the HTML tool to view/edit the HTML code directly, if you'd like.
Or, even easier, myself and the rest of the vCampus team take care of re-formatting posts when need be
I know we recommend IE, but Firefox has built-in spell checking on most web forms (including the vCampus discussions).