On MS Natural keyboards, these functions work as a combination of the Windows-key (with the little flag on it) plus the R,E etc.
Did someone load drivers or software for that, or is maybe your Windows-key stuck?
Found this info that may help you disabling it:
Windows Logo hotkeys disabling
Here is described a not documented system policy, disabling the use of Windows shortcuts, which is valid in Windows 9.x, Millenium, 2000 and XP.
This system policy blocks the "Windows Logo" processing in shortcut keys. However, after this policy is enabled, the single "Windows Logo" keystroke, which calls the "Start" menu, will be processed. It is necessary to emphasize, that when this policy is enabled, the "Windows Logo" keystroke in shortcuts key combination will be ignored, other keystrokes will be processed as usual.
To enable the policy the DWORD-type parameter "NoWinKeys" must be created in following system registry branch: "Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" and its value must be set to 1. Putting "NoWinKeys" parameter to 0 or its absence disables the policy.
This parameter can be stored either in the hive HKEY_CURRENT_USER, or in the hive HKEY_LOCAL_MACHINE and have the appliance scope either on the entire "Computer" (Local Machine), or on "Current User" respectively.
The policy having Computer scope, stored in HKEY_LOCAL_MACHINE hive of the system registry has priority over the policy stored in the HKEY_CURRENT_USER hive and having the "Current User" scope.