How to change the order of banners using the weight module?
Check out these modules :
weight

This module adds a weight option to enabled node types. Nodes with
lower weight will float to the top of lists, while heavier items will
sink.

Field_weight

Customise the weight/order in which fields on nodes can be displayed
on a per node basis and not just globally per type. Individual fields
can also be hidden from display.
For any node types that are enabled, a 'Field display weights' tab
will appear on nodes (for users with adequate permissions). From this
page administrators can customise the order in which fields are
displayed on each node by using a draggable table (or manually select
weights).

Nodequeue

The Nodequeue module allows users to collect nodes in an arbitrarily
ordered list. The order in the list can be used for a any purpose,
such as:

A block listing teasers for the five top news stories on a site
A user’s favorite music albums
A group of favorite from which one is randomly displayed

Nodequeue provides a simple drag-and-drop interface
to manually order any queue. Additionally, it allows nodes to be added
and removed from queues without needing edit permissions to the node.
Nodes can be added to queues either from a queue management tab or by
links on the node teaser.