wp_register_script and wp_enqueue_script

At least I should point you to so you can understand what will happen with http://codex.wordpress.org/Version_2.8:
Lester Chan’s Loading Javascript in Footer blog and Andrew Ozz’s Script Loader Updates blog

spstieng, to do that in the way you want, which, I think, is the right way, you have to:

1. Add the function to your functions.php file OR

2. Make a plugin just for that: to enqueue the script

For the scripts you mention, I think that enqueuing is enough, that is:

wp_enqueue_script('jquery');

For the difference between registering and enqueuing, see this recent thread in wp-hackers:

http://groups.google.com/group/wp-hackers/browse_thread/thread/5a14b1c37ebad6d7

(Scroll down to the 5th or 6th message, where the subject changes to exactly this difference.)