Drupal - CCK and VIEW

Use CCK and VIEW modules of Drupal:
http://learn.awakenedvoice.com/2007/07/30/drupal-cck-and-views-tutorial/
http://www.apaddedcell.com/creating-a-custom-home-page-in-drupal-using-views

- Make view column header sortable.

In Basic settings, style "table" has this option: click on the "*" to its right, in the style options panel, check "Sortable" checkbox to the fields that you want to be sortable.

- Add more fields to profile.

Default profile contains only account name and email. You can add more by using the Profiles module in Administer -> User management -> profiles.

- Show two fields in one column (The following is copied from this link):

By default, each field is its own column. However, you can place multiple fields in the same column. To do this, pick which field you want to represent the column, then pick another field and set the 'column' value to that field. You can place as many fields as you like in a single column, but only the main field in a column can be click-sorted.

This way, you can allow the user to enter first name and last name separately at registration, then show full name in a view.