Regarding the children issue, to me, a shower is pretty much an adult party. Now, sometimes it's ok for kids to be there, mostly if they are related to the GOH, or I've often seen infants at baby showers as the Mom-to-be has friends who are at about the same stage of life as she is.
But, just as in any other situation, if the child is unable or unwilling to behave properly, they don't belong. This business of opening the gifts for the GOH or making a fuss of any kind about the gifts, or about anything, is inappropriate and the parent(s) should immediately remove the child, even if it means leaving the party early. If I were the host, I'd see to it that the child was removed. Period.
When parents allow their children to display inappropriate behavior and make no effort to control them, they should suffer the consequences of being asked to leave.
As far as the hubbub of the crowd, my experience is that so much depends on how the host is running the gift opening and how the GOH is doing it. I've been to showers where it can actually be (at least somewhat) entertaining and engaging, and some where, frankly, the conversation with someone sitting next to me, no matter how mundane, is more interesting.
I think it's possible to hold the attention of the guests, but it takes some effort on the part of the gift opener and her helpers.