there is an easier way to do logging...
use the webservers logging method, logs will grow rapidly but it will not effect the performance of your sql server... (it WILL affect performance of your webserver)
To query all sorts of stuff from this log you could use a program like analog...
a superb logparser wich has an immens amount of possibilities.
logging to sql has it's pro's.. but i don't think they weigh against the con's (like huge tables and sql server load).
almost anything you can do with logs in a sql server you can do with analog
http://www.analog.cx/
check it out... it rulez! 🙂