Arduino UNO and accelerometer?

I am going to buy an Arduino UNO... And I need an accelerometer (in order to register movements)... I found this: http://store.arduino.cc/it/index.php?main_page=product_info&cPath=16_19&products_id=97 1) Is it precise? does it reveal little movements? 2) can I connect it directly with Arduino UNO, or do I need the Sensor Shield (http://store.arduino.cc/it/index.php?main_page=product_info&cPath=16_18&products_id=89)

Thank you...

1) Is it precise? does it reveal little movements?

For these kind of questions the manufacturers invented datasheets, it takes some time to learn reading them but its worth the effort.

how little is little ? Your requirements are at least not precise :)

can I connect it directly with Arduino UNO, or do I need the Sensor Shield

With appropiate wiring it can connect directly to an Arduino, a tinkershield might be easier. A breadboard is even easier imho.

The first you do with a product like this is identify the chip (here the LIS344AL) and go to google and type “LIS344AL datasheet pdf”