Some time I have some question that are opinion based, but I need to know what good programmers think what is better to do on that situation.
So is there any stackexchange subdomain that I can ask opinion based questions !?
As two of the comments mention, no, there isn't a site to ask opinion based questions. See here, here, and here for more information on that. However, Stack Exchange does have a chat where these discussions can happen. An example of one chat room would be the Programmers main chat room, The Whiteboard.