Redirect user to desired node after login?

Scenario: A user chooses to view a node without being logged in. I want my website to redirect the user to a login page, and then after logging in, return to the requested node. If the user enters the wrong login info at first, I still want them to be able to view the requested node after they provide the correct info.

I have both a login block on the very first page of the site, and a separate login page (a node) which is viewable to users who have not logged in.

I am very new to Drupal, but have implemented this functionality before without Drupal (using just php). There's a few things that I'm trying to get under my control.

1) Being able to designate a page to redirect to when the user tries to view a node and is not logged in. For instance, I would like the user to go to /login_page&destination=/user/node/### provided I have my separate login_page (cck node type with input set as PHP) created. I have tried to implement this by editing page.tpl.php for my respective theme (by setting a condition for if (!$user->uid) and using the traditional header(Location: ...) PHP redirect method. This does not seem to work however, as any page I try to access (existing or not) while I am not logged in redirects me to what I am calling home. Any ideas how to override this incorrect redirection?

2) I want to add some PHP into my login_page node to be able to retrieve the GET field "destination" (from part 1). I have specified that the code I am entering is PHP code, not HTML, but when I submit the code and view the node, the " ... " tags and code are still viewable in the HTML source; they weren't even parsed. Anyone having this problem?

3) I want to be able to modify my login block to be able to accept the destination URL as a GET parameter (or use Drupal's drupal_get_destination(); method). The problem is, drupal_get_destination() returns the node that I am currently viewing my login block from. I've tried previously being at a node and then going to the login block. This kind of makes sense as I'm not arriving to my block as a form action, but what is the correct use of this function? Also I've tried the traditional global variable $_SERVER['HTTP_REFERER'] in this block, but the value always appears as blank. By viewing my browser status, it seems there may be at least one or two degrees of PHP redirection; would this lose the HTTP_REFERER information?

If anybody has any ideas to help me in any of these parts, or provide a much easier alternative, it would be much appreciated. Thanks.