[devote]

function filter( arr, min, max ) {

    var end = [];

    for ( var key in arr ) {

        if ( !isNaN( parseFloat( arr[ key ] ) ) && isFinite( arr[ key ] ) ) {

            if ( arr[ key ] >= min && arr[ key ] <= max ) {

                end.push( arr[ key ] )
            }
        }
    }

    return end;
}

var massive = [2, 'crack', 3, 6, 'find', 2];
var filter_end = filter( massive, 0, 5 );
alert( filter_end ) ;  // 2,3,2