Safely drilling into a stone fireplace?
You'll need some quality masonry drill bits or some diamond core bits depending on the size of the holes you'll be drilling.
The hammer drill you picked out will do the job, just take your time, let the drill do the work.
You do not want to use molly anchors. They are for drywall or plaster hollow walls. Personally, I'd be using lag shields, 3/16&quot;, and lag screws. Their length depends on the size wood panel.
Drill into the stone, not the mortar. The mortar will crumble with the anchors.
And for God's sake, wear safety goggles!!!