I was interested in making a smoke detection unit which starts taking a video and also sends an SMS once the detector detects smoke; the problem is, which smoke detector should I use? Also, how do I connect and program this? I'm thinking of using B+ and using an MQ-2 sensor, should I also use an Arduino for this?
just use FC-22 type MQ2 sensor. It has both Digital and Analog output. For a precise measurement you can do analog-digital conversion using MCP3008, But to keep things simple you can just use the digital pin to detect if there is smoke. You can also set the sensor sensitivity by a variable resistor on the sensor.