Jon
I have had CCTV now for over 10 years.
You can buy cheap systems but the image is poor.
The better cameras are dearer but worth it.
I would not buy from maplin, the camera spec when i have checked is never better than 420 TVL (television lines)
The more TVL the better the image.
You have mentioned day and night systems, so you need infrared cameras, or seperate infrared lights. I also have automatic lighting. I can recomend the misnamed wireless floods from screwfix, i have four to cover most of my property, when the pir is operated the flood lights up, you can also slave off it lights up to 2kw. When the pir is operated it transmitts a wireless signal which chimes via a mobile unit in the house.
This is your alert that someone is on your property, man or animal. Take care when installing as the sun can cause false triggering.
That takes care of the lighting, both visable and invisable, infrared is seen by the camera, but not the human eye.
I would recommened a minimum of 480TVL cameras colour, the day/night cameras as they are known, give a colour picture in good light, but only black and white at night via the infrared LEDs built in the camera.
The recorder comes in many options since i bought mine, you need to study the spec to find what suits you, the price increases with spec.
I have a basic system thats records up to 25 FPS, if you set it to less, which i have to to cover two week away, then the image is jerky, but still usuable. It has date/time stamped recordings.
The best advise i can give is buy the largest hardrive you can afford, i have 120gb which is ideally two small, i would say 250kg min.
All four cameras are displayed on a monitor in a quad screen.
It is remote controlled and you can programe time and day for playback, i also have a link to my tv hard drive to put images on to DVD. But have i have said other options are available now at reduced prices to when i bought mine, built in DVD recording for eg.
With the cameras you need to study which lens you require, i have two at around 4mm, and two at around 3.5mm, this gives a wide spread but the images look smaller than they are, this may not suit you.
www.y3k.com/
www.iviewcameras.co.uk/
www.cctvdirect.co.uk/CCTV+Kits/Domestic+CCTV+Kits.htm
I have bought from y3k, about 5 years ago.
Also iv.
The last site i was looking at to update my system to six cameras/ 8 camera screen. And the system packages struck me as good value, but not bought from them.