Hello I think tha you'll better use an echo and to use simple cotes for your variable from POST :

Code:
print "Your first name is $_POST["FirstName"].<BR>\n";
[color=blue]
becomes
Code:
echo "Your first name is $_POST['FirstName'].<BR>\n";
or

Code:
echo 'Your first name is '.$_POST['FirstName'].'<BR>\n';
bye...