Hi Larry - yes, your antenna should be grounded for safety. Here is a thread that discusses grounding, which may help you.
http://forum.tvfool.com/showthread.php?t=901
No personal experience with the Lava antenna, but the gain numbers you posted seem absurdly high. They may be reporting the actual antenna gain (sensitivity) plus the amplifier gain. If so, this strikes me as a) intentionally deceptive and b) hiding the real number of interest, which is the antenna gain. An amplifier does not improve the signal; it simply takes what ever signal and noise is there and amplifies both, adding a little more noise of its own. An amplifier can be helpful if the loss of signal due to a long cable run is large compared to the signal quality, or if you have a splitter downstream which will also attenuate the signal.
Here are some old posts about the Lava -
https://www.google.com/search?q=site...m+lava+antenna - I'm not an antenna engineer (though I a am an engineer), and have no personal experience with the Lava.
You should have no trouble receiving the green majors on your plot. If anything, your amplifier is overloading your TV tuner and it's occasionally breaking up. A NM of 60 is more than 1000 times more signal than you ideally need. Just point the antenna north, even indoors unless you live in a cave ... you should have plenty of signal. Can the amp come out of the circuit? It has to come completely out for this test - you can't just unplug it. Connect your antenna's downlead to directly to the TV, if you can.
Also, you say you installed; where, on the roof? Pointed how? What are the surroundings? Your antenna has a front and a back, and you'll need to point the front toward the stations you want.