Start Konqueror by hotkey in KDE4

How to start konqueror by pressing hotkey combination, e.g. Win+E ?

Start System Settings,
click Advanced tab,
choose Input Actions,
press New Action (button on the bottom toolbar),
in General tab choose Name for your action,
in Action type: Keyboard shortcut -> Command/URL (simple),
in Keyboard Shortcut choose your shortcut, e.g. press Win+E,
in Command/URL Settings type your command (with full path if neccessary), e.g. konqueror,
press Apply (right bottom corner).

If the above description does not apply to you (e.g. KDE 4.2.2), try:
System settings
Input actions
Right click On the left panel
select menu Hotkey settings
select New Global Shortcut
then Command / URL
name your shortcut and press Enter
click Shortcut: None button (right bottom bar)
press your shortcut, i.e. Win+E
click on Command / URL dialog
paste command, i.e. konqueror

Test your shortcut, e.g. press Win+E