With modern brake pad materials there is no need for slotted or crossdrilled rotors even for track use. The only reason you see them on Ferraris etc... is because people expect to see them there!
If you want to shorten your stopping distances on the street
1) get better tires
2) get autoslalom/solo II front brake pads from Williams Performance Friction.
3) to cool your brakes better, remove the splash guards/dust shields that cover the back of your rotors.
Williams made a set of front brake pads for my Insight for only $75 canadian.
These are solo II pads so they are powerful when cold, so they are great on the street. Track pads need to be hot to work properly, when cold they are weak and wear out quickly.
I'm planning on installing them this weekend.
http://www.wpfri.com/