FulkrenHi All
I've been struggling with the white text on a white background issue on a new install of WP and none of the fixes I googled worked. So for all you future frustrated WP admins out there, here's the solution to my particular problem: The culprit was Magic Quotes.
My system:
Windows Server 2008 R2 32bit, IIS 7.0 and PHP 5.3.5 running on FastCGI with WinCache 1.1 running a brand new install of WordPress 3.1 with no modules installed or activated.
With magic quotes on, I had white text on a white background in the editor box, several broken buttons, and could not activate HTML editing. Turning MQ off resolved all my issues.
If this doesn't fix it, the most common other reasons for this issue that I found were:
1) Missing files in your WP install - fixed by downloading a new copy of WP and replacing the incomplete copy.
2) WP Module messing with TinyMCE - fixed by disabling and deleting additional modules until the culprit is found. I've read that you must physically remove the modules, as just disabling them doesn't always truly remove them.
I hope this helps anyone else who runs across this issue. I know it was frustrating the heck out of me.
Fulkren
camelCoder