Many of our favourites have been mentioned. I love Where the Wild Things Are, The Elephant and the Bad Baby, and Tabby McTat :)
Two more that are perfect for bedtime (with 2.3 year old dd) are:
YAWN by Nick Sharratt and Sally Symes, in which a very contagious yawn is passed from baby to cat to fish to bird to mole to elephant, and inevitably to the toddler being read to. The yawn itself is a big round hole in every page, which my dd seems to get a kick out of, and by the end of the book all the animals decide that it's time for bed.
Tuck Me In! by Dean Hacohen and Sherry Scharschmidt, in which the toddler gets to tuck in a series of cute baby animals by turning half-pages made to look like cozy blankets, before coming to the end of the book when it's his/her own turn to be tucked in.
We read three books at bedtime and the first two can be anything that dd chooses from her bookshelf, but we usually try to make one of these the last book we read - they are both such great transitions from story to bedtime.