- If you want to format for Mac only, use Disk Utility (Applications>Utilities folder) to format the drive as "Mac OS Extended (Journaled)" with a single GUID partition.
- Not that I know of. It's likely that the drive is formatted as NTFS - if that's the case then you can use it with both Windows and Mac machines using Paragon NTFS for Mac: a little $20 app that will allow you to both read and write files to the volume using your Mac.
Hope this helps,
.DS_Store is an invisible file - a small file that store information about a Finder window, comments, etc. (they're in each folder, on the Desktop, all over).
I have no idea why the Finder is trying to copy an invisible file. Maybe that's what the Windows formatted drive is choking on. I only know of a temporary fix (others, smater than myself, may know of others) and that's to show invisible files and choosing not to select .DS_Store. If you want to show all invisible files, open Terminal in Applications>Utilities and copy and paste:
defaults write com.apple.Finder AppleShowAllFiles YES
and then restart. You'll be able to eliminate copying .DS_Store files because you can see them.
In order to make those invisible files invisable again, copy and paste into Terminal:
defaults write com.apple.Finder AppleShowAllFiles NO
Hope this helps...