Accelerometer with arduino

Hello to everyone. I'm new in this forum; im starting my final project in my career (Electronic Engineering). In this project i have to measure the acceleration in order to decide if a person has fallen. I wanted to use Arduino hardware and software because i believe it is important to support open projects. My question is, which Arduino board should i use and if you can recommend me documents to read to understand better the arduino world. Thank you very much.

Wikipedia has a very nice explanation: http://en.wikipedia.org/wiki/Arduino

The most common Arduino board is the Arduino Uno : http://arduino.cc/en/Main/ArduinoBoardUno

To learn how to use it, start at the main site http://arduino.cc , and read how to install Arduino. Also check the reference to see what functions are available. Once you have installed Arduino, there are many example programs. The most simple example is a blinking led (In the file menu: examples/Basic/Blink). If you can get that led blinking, you have made your first program. From that point you can go on.

In the 'Playground' section (see the bar at the top of the Arduino website) are some accelerometers mentioned. Some have analog outputs, others use the digital i2c communication. http://arduino.cc/playground/Main/InterfacingWithHardware#motion_accelerometer