Belgian beers - to chill or not to chill?

Hi,

Although the shop at the end of my road has an excellent stock of 
bottled British ales (not to mention a constantly-changing cask), 
tonight I decided to try something different and came home with a kriek, 
a gueuze, and something that calls itself "****ge Belgian Imperial Stout" 
at 10.5ABV.

I know basically nothing about Belgian beer, so I'm unsure whether these 
would best be served chilled, or cellar temp, or at room temperature. 
Suggestions?

Pete