Answer: toss your book. Its too old to work with (now 4.5 years old).
The error on an html element in eclipse is likely the use of deprecated HTML (border in table). Use CSS.
The problem with the PHP is it expects you have register_globals enabled. This directive has been disabled by default since 4.2, deprecated in 5.3, and removed in 5.4. As pointed out, all of your data must be extracted from a superglobal, which in this case is $_POST. You can however use isset() to check multiple conditions by giving all the arguments you expect, then within that block extract all the variables and process per normal.
header('HTTP/1.1 420 Enhance Your Calm');