Is it possible to Stop jqGrid row(s) from being selected and/or highlighted?

Use the following code:

beforeSelectRow: function(rowid, e) {
    return false;
}

If you, like me, have a gazillion jqGrids and don't want to override onSelectRow for every single one, here's a global version of Reigel's solution that worked nicely for me:

jQuery.extend(jQuery.jgrid.defaults, {
    onSelectRow: function(rowid, e) {
        $('#'+rowid).parents('table').resetSelection();
    }
});

try:

onSelectRow: function(rowid, status) {
    $("#grid_id").resetSelection(); //Resets (unselects) the selected row(s). Also works in multiselect mode.
}

you can read documentations here. Hope it helps you...