This is one of the instances when you may need to store the address data in multiple locations: the Customer Table AND the Order Table.

You can set up a one-to-many table for, say, your customer addresses so you can store both old and current addresses.  When a customer changes address, you ADD the new address and KEEP the old one, instead of changing the old to the new.  Old records that use the old address will stay the same so they won't be affected, while new records will use the new address going forward.  This is a variation of Richard's rule "Do not delete anything."

The address table may look something like:

CustID     AddrID     AddrNote     Address
1000       1          Old           .......
1000       2          Current       .......
1001       1          Old           .......
1001       2          Current       .......
1002       1          Current       .......

Is this the way the address Table should look?

That is the general idea.  Also, you need to have a way to prevent the users from choosing an old and invalid address, obviously.

How can this be done (Choosing Correct Address)?

You can hide all the old addresses in your combo box so that user can't choose them.  The combo box's row source could be something like:

     SELECT * FROM AddressesT WHERE Description <> "Old" AND CustomerID = ...

This is one of those instances where I would say to definitely copy the customer's address to the order table so that you know what their address was at the time the order was placed or shipped. I cover that in the extended cut for Invoicing.

Thanks! This works just fine. I thought about this a few days ago, but couldn't wrap my head around it.