Sorry about the double post. Pretty dead around here anyway.
Well, I finally figured it out!!! Where the wall and the piano disappear. In season 1 episode 16 Star-Crossed Lovers and Other Strangers the wall between the living room and the vestiblue is still there with the piano up against it, but in season 1 episode 17 The Breakup Part 2 the piano is gone and the archway between the living room and the vestibule is now there. I can't believe that I finally figured it out. Now, if I can only remember it. lol
Pretty Town Spinster: Did you ever remember who you lent you DVDs to and get get them back?
Opps, I think I made a mistake. The piano is gone and the archway is put in in episode 18 of season 1 The Third Lorelai. If there is anyone out there who can verify this, I would greatly appreciate it. For some reason this has really been bugging me for a loooong time.