That's kinda bizarre...does your page have a character set selected?
[HTML]<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />[/HTML]
If that's not it, try inserting it into the database with the function addslashes:
Code:
addslashes("This is the string I'm trying to input");
Lastly, if that doesn't work, make sure you're using the standard ascii ' symbol and not some strange variation like word puts in...