Need Category Table Implementation Help

Hi

I new to sql procedures and I need your advice on below subject. Thanks in advance.

I have products table that has catid (string 50) and subcatid (string 50) I like to transfer the string to another table (categories) and keep only int values in products catid and subcatid.

therefore I created categories table and added 3 fields;

catid int (primary and autonumber)
catname string 50 will be equal to category name in products table
parentid int (if it is a parent category, it will be equal to 0 otherwise if it is a subcategory it will be equal to parentcatid)

so instead writing a vb program I like to ask your advice on better solutions.

please help

Also I am using sql express 2005 and I wanted to practice (learn) sql DTS. is there any way I can download this package and work it with my system?

thanks again
Cemal