I was getting the "run disk" error, too. Here's how the install worked for me for Microsoft Mappoint 2004 (North American edition).
I burned CD 1 as a data disc (and I did not give it a volumn label).
I burned CD 2 as a data disc, but it will only work if you give the 2nd CD the volumn label "GEO11NA" (without the quotes).
(For the european version, the volumn label for the 2nd CD needs to be "GEO11EU" (without the quotes).
NOTE: For Microsoft Mappoint 2003 the 2nd CD's volumn label would be GEO10NA (North American version) or GEO10EU (European version).
For Microsoft Mappoint 2002 the 2nd CD's volumn label would be GEO09NA (North American version) or GEO09EU (European version).
Hope this helps,