As far as antenna selection is concerned, I would opt for an outdoor mounted Winegard HD7696P. I'd use 150° magnetic as my starting aim point. If my initial reception testing at the antenna showed reliable reception of one or more of the signals in the red section of the report, and I had interest in their programing, I'd install a CPA-19 preamp at the antenna also.
The HDHR is a great tool for antenna alignment.
http://forum.tvfool.com/showthread.php?t=820
I have no intense loyalty to a particular brand of splitter. My experience with the Ideal brand product stocked at the local big box store has been completely satisfactory. For your system, I'd suggest a 3-way splitter with a bandwidth rating of 5 to 1000 MHz (though if the price for a satellite grade splitter is the same... that's fine too).
http://forum.tvfool.com/showthread.php?t=13090
AS far as grounding is concerned, my opinion is that best practice is to ground the antenna system regardless of whether it's in the attic or outdoors. The goal of grounding is to prevent a difference in voltage from developing between separate pieces of equipment if there is an electrical fault. For example, if you drove a nail or screw into a wall and by chance, it pierced a power cable and coax, you could expect grounded coax would provide a path for fault current sufficient to trip the circuit breaker. An ungrounded coax would simply conduct the power line voltage to all parts of the antenna system... setting up a potentially dangerous trap for some who may latter touch some part of the antenna system.
http://forum.tvfool.com/showthread.php?t=901