Not all of these files are created by default, some are only made when you access the directory with a particular application, but a quick explanation of them:
.com.apple.timemanachine.donotpresent - Disables the Time Machine dialog which asks you if you'd like to use that specific disk for backing up data.
.DS_Store - Created by Finder when you open a directory. It stores information about the folder (view options, icon positions, etc).
.fseventsd - created by the fseventsd daemon. It contains data about file system events such as modifications, deletion, creation, etc.
.Spotlight-V100 - stores indexing information for spotlight in the form of metadata.
.Trashes - A folder containing files that have been sent to trash but not yet deleted from the volume.
It's fine to delete them, however any settings you currently have for the folder will be erased. Any files on that volume that you sent to the trash will be permanently deleted. I'd suggest keeping them.