Fulltext search

Hi all
What is the best situation for using full text search instaed of of searching? I have a table with a varchar(200) coloumn and table has lot of records.when i try to search a word it takes a long time for example when i type select * from tableName where descript like '%tt%' it takes more than 5 seconds.
I wonder that is it neccesary to use full text search on this table?
thanx in advance

I would recommend to use full text-search. please check whats on msdn for full text http://msdn.microsoft.com/en-us/library/ms345119(v=sql.90).aspx