Reading all of this has made me think I should perhaps be looking for an inexpensive machine "just in case". I think my DIL has the one my mother had, an old New Home that sewed straight seams very well. Maybe I should get it back. I also have thought about leaving it there and teaching my granddaughters to sew next summer when they are 6 & 7. Oh, decisions, decisions, decisions! Guess I will go eat some chocolate and figure it all out.
Good luck on getting your machine back in order!