OS X :: Dragging Multiple Selected Items?

As a newbie to the Mac but with Windows experience since 1990, I am finding the most subtle things the hardest to get used to. This post is about dragging items.

1. The first thing I am still getting used to in dragging a single item: in Windows a highlighted item can be immediately "clicked and
dragged." In OS X, it appears that very often you cannot drag an item unless you pause for a fraction of a second while on the item. However, the "fraction" seems to vary, sometimes being very short, and otherwise being longer. The result is I have to frequently try several times to get the object to drag.

2. Even worse, when multiple items are selected, it seems that sometimes they cannot be dragged no matter how long I pause. The action of attempting to drag simply un-highlights the items.

While I am typing this comment, I am trying to drag items in Mail. I have multiple items selected, and most of the time, anything I do to try to drag them fails, but simply reverses the selection on some items. On a rare occasion, the drag function works. It seems sometimes if I start the drag slowly, it works. I am still assuming that this failure is due to my lack of skills. But my instinct is to consider this a bug. What is the correct way to drag multiply selected items reliably?