Smart surveillance system?

I and my husband are software professionals. Due to the hectic work, both of us reach back home only very late. Our parents are staying alone. They live far from us. As they have turned very old now, we are little scared to leave them alone at home. So we have planned to install a security system at home.
While browsing for the latest security technologies, I came across an interesting article that speaks about the security systems for the home. It says that installing CCTV cameras can help you monitor the house so that in a case of any emergency you can do the needful. Could you please suggest some good companies that provide security service? My friend suggested one of the CCTV camera solutions in Vancouver. Could you please share some suggestions for choosing the best surveillance system? Do you have any other ideas on installing a security system? Thanks for suggestions.