populating <select> and searching to criteria

Hi People, I have a three part question here. Well actually its 3 separate questions. First. How would I populate a select menu from a mysql databse with the entries from a particular field, but only showing those that are unique, ie not showing more than 1 of the same value. Second. How would I then have one of those options selected depending on what it contained in another table? Third. I need to understand how the following would be achieved. In the database there is a text field that contains a number of 'keywords' I need to be able to search through those individual keywords and return results based on a % match from the original search. Ie if I search for 'secretary, typing, customer relations' I need to return all records from the database that has one or all of those words contained in the text field and display them as a % match of that search, ie if 1 match then 33% 2, 66% and so on. Any help on the above three would be fantastic. Cheers, Shannon