photo album and tagging

[therob1]

hi im new here and could do with a helpful nudge in the right direction.

 

ive managed to create a simple photo album site and have 3 tables (category,images, and img-cat) set up to deal with the tagging of items with in each photo using check boxes. the two things i need help with now are:

 

[*]how can i create sub category's for each category using the 'link' table ? ie group 'people' and maybe have a master check box to check/uncheck all people then another box for 'places/locations' etc etc

[*]how do i get the MYSQL db to preselect items that have been entered into the DB with a 'tag' already?

 

thanks in advance for your help!