Module development and code questions

Hey everyone,
This post is to solicit feedback in solving a problem that I currently have. I am assuming that I will have to build a module to do what I need, but I would like to get other people's input as early in this process as possible so I can make better decisions right away.

Here is my problem:
I am rebuilding a large community site that caters to backpackers (primarily in Europe). We will have a large amount of information (much of which will be user generated) that needs to be categorized to a location. For example, if I am traveling to Paris, France, I will want to get as much info about the things to do there and other peoples experiences as possible. Because of this I want most (if not all) of my content to be localized.

I have the following situation:

I want to show records from a table as follows:

(select id, name, age from person)

Name Age
name1 [ ]
name2 [ ]
name3 [ ]
name4 [ ]
. . .
nameN [ ]

(SUBMIT BUTTON)

Age are textfields associated with the names.

I want to validade all age fields, set invalid ones with red border and return only one message ("Fields marked in red are invalid") for all the inconsistent (not numeric and negative, for example) Ages.

I posted this over three weeks ago on "Post Installation" and got no responses...perhaps it is more complicated than I had thought...

I would like my users to be able specific info on, for example, all the theme parks they've been to. So for each park, I'd like them to be able to input info like the city, state, review, maybe even a photo.

I've been writing modules and little hacks for Drupal for a while. I'm playing with data structures, and am confused as to the convention for '#properties' versus 'elements'. I don't seem to be able to find anything useful on the subject, but seemingly people know what the convention is, so here's me asking...

As an example, let's say I have a data structure that holds a title and either a $form style structure, or a callback that returns one. There may also be some other config type info in there. Here's my data structure as it is now:

Hi

I've managed to get some information to display on the user's profile page with a heading (like the 'History' bit), but I was wondering if it was possible to get the information to display on a new tab of its own? Is this done in the _user hook?

Many thanks
Dan

Hey, guys ,currently i am developping a site based on drupal, for some reason i have to create file which is separate from drupal. However i want to still use drupal's database function for consistancy. thus i include the bootstrap function.

require_once './includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_DATABASE);
....

this works fine if i put it under the same directory as index.php
however if i put it under a sub folder and change it to

require_once '../includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_DATABASE);
....

i got this error
Warning: include_once(./sites/default/settings.php) [function.include-once]: failed to open stream: No such file or directory in E:\xampp\htdocs\drupal\includes\bootstrap.inc on line 238

Warning: include_once() [function.include]: Failed opening './sites/default/settings.php' for inclusion (include_path='.;E:\xampp\php\pear\') in E:\xampp\htdocs\drupal\includes\bootstrap.inc on line 238

Warning: require_once(./includes/cache.inc) [function.require-once]: failed to open stream: No such file or directory in E:\xampp\htdocs\drupal\includes\bootstrap.inc on line 844

Fatal error: require_once() [function.require]: Failed opening required './includes/cache.inc' (include_path='.;E:\xampp\php\pear\') in E:\xampp\htdocs\drupal\includes\bootstrap.inc on line 844