Andrew wants to get WiFi to all corners of his house. Leo says that's a non-trivial effort. He advises using WDS and repeaters. WDS stands for 'Wireless Distribution System' and is a standard spec devised to do just that. He'll need repeaters everywhere to extend the signal. It helps to have the same brand repeater/extender as the router he uses. Andrew says one wireless access point isn't getting a reliable connection. Leo says it's because it's weak. So putting a repeater about halfway would be a good idea. Leo recommends using a Wi-Fi analyzer utility to see which channels are best. If he's on a Mac, he can try NetSpot. EkaHau is a Windows alternative.
He could also look into just wiring up his house, which would provide a more reliable and faster connection.
The next caller recommends getting another router and using it in access point mode. Also, getting a dedicated access point is a better option.