Aight man - this is a little crazy, but try this...
Find every charactor that is causing problems
Use this command:
ereg_replace("&","ampersand1212", $content);
This takes the variable '$content', finds any instance within that variable where '&' is used, and replaces it with 'ampersand1212'
I use wierd things like ampersand1212, because it is VERY unlikely anyone would type that if they wanted to communicate any idea in a clear manner.
When reading from the database to output use the same command, but switsh 'ampersand1212' with '&' like this:
ereg_replace("ampersand1212","&", $content);
hope this helps,
Lazzerous