What temperature is ideal to store my beer? Is there a difference depending on the beer type?
The ideal temperature for storing beer is between 10 to 15 ˚C (50 to 59 ˚F). If you are planning to preserve your beer for several years, it is better to have an even lower temperature of about 4 to 10 ˚C (40 - 50 ˚F).
A cold cellar is ideal to preserve your beer as a humidity of about 60% - 65%. The reason being that it can affect the airtightness of the cork (or cap). Dry corks are bad for preserving beer as they will tend to break down and cause wild yiests or bacteria to enter the bottle (which would render the beer undrinkable).
And as commented by Grohlier:
Remember, light can drastically affect beer. Darker bottles can withstand more light than their green and clear counterparts. However, light is not good for beer in general, even if it is stored at the appropriate temperature.
If the beer has been conditioned/pasteurized then you should store the beer as cold as possible - 2-5C is good. The biggest negative factor affecting beer storage is oxidative staling, and this proceeds 3 times faster for every 10°C/18°F increase in temperature. Inversely, each drop in temperature of the same amount causes the rate to reduce by the same 3-fold amount.
If the beer is still living, then storage temperature will depend upon if the beer has fully conditioned, for example, storing at 15°C until the beer is conditioned and then dropping to lower temperatures.