First of all, I am also only aware of the 2-CD release of LROOE. I'm afraid that the person at JBHiFi may be misinformed. If there is/was any single CD, it is not an official release by the band - it is an unauthorized bootleg.
As others have said, the original version was a tan cover with two-CDs containing 20 songs. Then a deluxe version was released with a red cloth cover which contained Hole In the World and Please Come Home for Christmas. It also included a very nice booklet with additional photos.
So Bramwen, you are free to believe this guy if you want, but we hardcore fans are pretty well-informed about these kinds of things. If the band released a single CD version, it was the world's best kept secret, which doesn't make a whole lot of sense, does it?