IIS Plug-in

I think I might be better off changing my URL formatting.
Current:
http://mysite.com/team_schedule.asp?tid=10&yr=pos03

But most articles I see say make it something like this:
http://mysite.com/team/10/schedule/pos03

Better indexing, and also easier to change technologies later on (as there is no whatever.asp, whatever.php, etc.).

So, I saw this:
http://www.isapirewrite.com/

But is something like this needed? Can't I just read the URL entered and parse it? Or is that considered "sloppy"?