Here's what you are looking for:


Show Time,Date,both or Battery on top bar at Today screen
[HKLM\Software\Microsoft\Shell\]
Time:
"ShowTitleBarClock"=1 / "TBOpt"=1
Date:
"ShowTitleBarClock"=1 / "TBOpt"=2
Both:
"ShowTitleBarClock"=1 / "TBOpt"=3
Nothing:
"ShowTitleBarClock"=1 / "TBOpt"=0
Battery:
"ShowTitleBarClock"=0 / "TBOpt"=1