1 - Trial of the Champion (First run)
2 - Culling of Stratholme (First run)
3 - Halls of Reflection (First run)
4 - Escape from Dunholde
5 - Opening of the Dark Portal (Black Morass)
Top 3 because I hated them with a burning passion. Bottom 2 because you couldn't skip or speed up the instance in what was otherwise a relatively decent pair of instances.