Is it possible to upgrade 2.26 GHz processor to 2.4 GHz?
Sorry, the MacBook Pro processor is soldered on and removing it would likely destroy the logic board. I still have a 2009 MacBook Pro and it's fine, not to say that I wouldn't want a newer MacBook, though.

Btw: Get an SSD for it. Replacing the hard drive with one cut boot up time in half for me. I personally recommend Intel.