Copy selected file name without extension to comments.

name-to-comments.applescript

tell application "Finder"
	set theFile to selection as alias
	tell application "System Events" to tell disk item (theFile as text) to set {theName, theExtension} to {name, name extension}
	if theExtension is not "" then set theName to text 1 thru -((count theExtension) + 2) of theName -- the name part
	
	set comment of theFile to theName
end tell