We are using MOSS. I have several lists where I cannot enter new items using
Edit in Datasheet but there is no problem entering new items using the new form.
I first found this with task lists, but now in testing realize that even if I
create a new Custom List without adding any metadata I cannot insert records
using datasheet. I receive the error "Columns that require data are not included
in this view. If you want to edit or add rows, you must first add these required
columns to the view." I modified the view to display all fields and then get the
error message "You must enter a non-blank value in the Name field". Where did
this Name field come from? It looks to be an internal id because the value is
1_.000 for the item that I entered using the New button. Why would the list have
an ID field and this Name field?

This issue only occurs with newer created lists, and only on some site
collections. If I create an OOB custom list on my Mysite (different site
collection)I can add new items using datasheet view without a problem. I tried
to save this Custom List template from my MySite and import into list templates
on a site collection with the datasheet issue, however when I create a new list
using that template I get the same error message and I see the Name field when
modifying the view (but I do not see the Name field on MySite custom lists).

I am not sure if my issue is related to list templates, site content types or
something completely different at this point. I'm hoping someone else will be
able to give me some suggestions.