There was a discussion of Christmas on the Life and Times board last December and I've linked Julie's post regarding Christmas traditions.

It's hard to tell how or if the shops would have been decorated for Christmas. The holiday was not celebrated as excessively as it was later in the century, but it was observed with some style as you can see from Julie's post. They might have been decorations (evergreens, most likely), but I don't think we have any concrete evidence one way or the other.