Normally those commands won't run unless you depress the Windows key at the same time. Check this web page from Microsoft which tells you how to disable it:
http://support.microsoft.com/kb/216893
You could always try using the keyboard in a different USB socket as this can make a difference in some things. What kind of keyboard is it? Does it need drivers ect? What about the new system, is the bios updated and any new firmware updated for drives ect?