I get a page with 3 menu items.
On the first menu when I try and click the submit button I get a 500 error.
On the first line of your cgi script, called the shebang line, the path to perl looks like this:
#!/perl/bin/perl
You should change this line to the real path of your perl executable maybe for windows it should be like this:
#!C:/perl/bin/perl.exe
or where ever you have the perl.exe file maybe here:
#!C:/xampp/xampp/perl/perl.exe
The second on submit an entry I get a 404 page not found error returned. This is a missing link when you click the submit button. Check the form submit button link.
The other item is a url entry facility to the guestbook I guess.
This has a permissions issue.
Set the directory and files to 755 on linux or on windows set them to writable, not readonly. In windows XP read only is usually the default.
Come back with actual error messages if you want more detailed answers.