For now the situation in the context menu of telerik is that when moving with the mouse pointer from one item to another, the child context menu opens. I want that the child context menu will open only when pressing the item and not when going over it, how could I do that?   

Hi runes,

We support ClickToOpen only for root level MenuItems in RadMenu not in RadContextMenu (RadContextMenu have ClickToOpen property but it is meaningless for it).
Both RadMenu and RadContextMenu have two properties: ShowDelay and HideDelay of type Duration. Just set them to some big value (ShowDelay="1:0:0" - one hour for example) and menuitem will wait an hour before it opens its popup or you will have to click it to open the popup instantly.

Let me know if you need more information.

Sincerely yours,
Hristo
the Telerik team