Jerry, If you can afford it have a professional install your alarm. There are a lot of instalation tricks that will give you better protection and reduce false alarms. Stay away from wireless systems if you can. Wireless systems are a quick install but require alot of maintinance over there life. Do you really want to worry about fifty batteries and transmitters in your house. Wireless communications are great but often expensive and don't usually provide detailed transmissions such as opening/closing,system trouble,medical,ect. If you use phone line communication back it up with an exterior siren or flashing lights. A person breaking into a home wants it to be dark and quiet. Security signage and fake cameras are also cheap deterants.
As in investing in a gun, take your time, ask questions, learn a little first.
Good luck