Scanning old slides

Today I finally started on a project I've been avoiding for years (because of the volume of work involved): scanning all my old slides into digital form. Several years ago I bought a scanner than handles slides and film, and I used it a bit but then got distracted by other, more interesting, projects. I have around 4,000 slides dating back to the 1960s, covering travels in Europe, North America, New Zealand, Australia and possibly North Africa. The quality of the scans isn't great, but in many cases this is because the colour in the slides has deteriorated over the years. Perhaps I'll use The Gimp to turn them all into sepia so they look even older.