Welcome to the wonderful world of Home Automation. Warning its very addictive.
Lets see:
Definitely fit a whole house filter.
Lighting - X10 can do this. But be wary that some transformers can't be dimmed, and the energy saving bulbs can cause interference with the X10 signal. Though the fitting of a local filter can prevent this interference. The new X10^2 modules are a definite improvement over the older type. While I haven't actually used their micro modules we install something similar which we call a mini-module its about 2mm thicker, slightly cheaper and has the same spec. These have all worked very well. We are also developing a special adapter so that either the micro modules or our mini modules can be Din rail mounted.
Heating can be controlled via a digimax thermostat, This can be coupled with an SC9100 alarm panel and your heating controlled via this. Up to 4 separate zones can be set up with the panel. You could use mains operated valves for each rad, and link them to appliance modules.
Security - The Sc9100 panel will give you basic security functions, and has a built in telephone dialler, so it will phone you when the alarm triggers, also you can phone the alarm and switch lights on or off. We also do a GSM module for this unit, though it doesn't support SMS messaging.
CCTV and access control. What sort of access control are you thinking of. And what type of CCTV system where you thinking of. Do you want to be able to access it via the internet, see it on your TV. How do you want to record the images etc.
To control it all, basic control functions can be done from the SC9100 panel. You can set up timers, there is also a random event timer which will turn something on around a set time I think its plus/minus 30 minutes of the stated time.
For more advanced control you have 2 choices PC based and non-pc based. I used and recommend the Homevision controller www.csi3.com This is a non-pc based system, though it does require a PC to program, and uses an XM10 interface rather than the CM11 or CM12. Homeseer www.homeseer.com is a PC based application which is very good.
If you require somewhere between basic and advanced control then the Active home software that comes with the CM11 or CM12 is not bad. Its not great and the Clock in the Cm11 loses quite a lot, over a period of 6 months it can lose about 45 minutes.
What about structured wiring have you though about this.
If you require more info or brochures etc, just PM me and I can send them to you.