When generating the trace, select save in table. I have never tried it because trace files work better for me. I have read about setting up stored procedures that are executed at the startup. A stored procedure can be used to start a sql agent job which starts a SQL profile trace. I would not recommend running profile traces 24x7.
Your question on working on blocking and cpu intensive SQLs is an article in itself. You might try searching for such articles or possible book on the subject. I often use the DMV's to find the most CPU intenstive queries and use profile traces to collect details about it.