depending on your son age.. if you want something afforadable and nice you can do it in one of the fast food restaurants like burger king or mac.. they will do the entertaiment and everything ..
if you want something else you can do it in one of the amuesment parks in the malls such as jungle zone or try gympanze in villageo ..
anyways hope u have a great time with your son ... happy birthday to him in advance..