The 2.53 GHz, $1,499.00 should have you covered. It has 4 GB 1066 MHz DDR3 SDRAM standard (vs. 2 GB on the 2.26 GHz model) as well as a 250 GB Hard Drive as well (Serial ATA at 5,400 rpm though you can upgrade to 320 GB for slightly more money).
The 2.26 is fine though you might want to customize it a bit and you wouldn't save much over the faster one.
Go with the base model if money is a bit tight. $300 is a big difference when you consider that you can upgrade to 4Gb RAM and a 320Gb HDD for $160 total --plus, you can keep the stock 160Gb drive as a Time Machine back-up (or sell it).
Comments
The 2.26 is fine though you might want to customize it a bit and you wouldn't save much over the faster one.
Do you like saving money? Does it have to be brand new?