Blackwork is not too difficult and is a good way to get used to reading charts. All the stitches are straight lines so there is nothing tricky about it. You can do the kind where you do pay attention to the back or the order you do the stitches. Then is a more complicated (but fun!) type that is reversible. This is done in rows referred to as 'trips'. You make a few 'trips' across the cloth in a particular order to make a design on both sides.
I think you should always start with something that really appeals to you. Then you are more likely to complete it!