Currently I really don't have anything I hate to train. In fact I love everything I'm doing.
There was a point that I hated to work my legs. They just hurt, and caused me problems. That situation has been worked, and I now relish training my legs.
If there was one part that I could throw away, it would be biceps. As it is I only do a few sets for them anyway so it's not a big deal. They are hit pretty good from the compounds that I'm doing, so a couple of finish sets is easy.
More than anything I'm just grateful to still be able to train.