Dialogue box won't go away

[nmr472]

I have recently installed Mint Nadia 14 on my old Lenovo R61 laptop.
I have initially installed Mint alongside Window Vista Business.

When I log onto Mint, there is a dialogue box with a list of things to assist new users, like tutorials, Manual, Known Problems etc. If I click on any of the items on that dialogue box the screen itself greys out and the topic I've clicked on comes up. But a grey oblong the same size as the original dialogue box stays on the screen which covers everything else on the screen. If I move the mouse over it the icon changes to the hand pointer, but nothing happens if I click on that oblong. I can drag other dialogue boxes out from under the grey oblong but I can only see the bits to the side or above or below the grey oblong.
If I click "close" when it first comes up then it closes properly and goes away, but not if I click any of the icons within it other than "close".

[xenopeek]

Yes, the Welcome Screen could do with an overhaul. There is nothing wrong with your installation, it is the program that has become a bit problematic when used on newer desktop environments.