why is the "buy all" no longer visible on my wish list? and it is not letting me delete items.?

The 'buy all' has, for some reason, been removed from the current version of iTunes - you can try leaving feedback for Apple and maybe it'll be added back in a future update :http://www.apple.com/feedback/itunesapp.html . Until then you can only buy items individually.

In terms of the 'x' for deleting items from it, other people have posted about that and it's affecting me as well. I assume that there is a bug with the current version of iTunes and/or a problem at Apple's end which they need to fix.