function myFunct(settings, callback){
   if(!callback)return;
   var x = 100;
   //here is where i have issues, as i want
   //to be able to adjust the success function
   // to also have 1 line of code, a decrementer.
   //I want to do something like settings.success = "x--;" + settings.success;

   callback(settings);

   //I also wasnt sure if you could wrap 'callback'
   //with a success function when the inner success function executes
}

var settings = "";//settings of the ajax call.
 myFunct(settings, function(x){ $.ajax(x);});

function myFunct( settings, callback ) {
    if (!callback) return;
    var x = 100;

    callback(settings).done(function(){
        x--;
    });
}
var settings = { url: "foobar.php" };
myFunct( settings, function(x) {
    return $.ajax(x);
})