As the title suggests, I want to start watching Ghost in the Shell. But I have seen many different ones and dont know if they're all part of the same series etc.
What are some suggestions for where to start the series?
I would suggest:
As mentioned above, the latter two items are set in a different but similar universe so can be watched individually from the first two. I recommend the movies first because the original GitS movie was intended to be taken in without pre-watchings, whereas I felt the television series made some assumptions about familiarity with the source material.
Hands down: Mamoru Oshii's original 1995 film, 'Ghost in the Shell'.