You can definitely get the 2.16 Ghz + 7200RPM 100GB HDD config at the Apple Store.
Interestingly, your best bet is if you have several stores around-- in my case the White Plains, NY store swore up and down that the 2.16 models were
not available in-store, a quick call to the Palisades store in Nyack proved that was not true-- so I was able to pick up the above config there.
Now, if you wanted another CPU version and the 7200RPM drive -- you have to go CTO.
Good luck,
JT