Hello:
You can log in as host and do so by creating a template file. Below are steps to accomplish this.
1) After logging in go to Host > SQL and run the following SQL:
SELECT
{ObjectQualifier_}Portals.PortalName,
{ObjectQualifier_}PortalAlias.PortalID,
{ObjectQualifier_}PortalAlias.PortalAliasID,
{ObjectQualifier_}PortalAlias.HTTPAlias
FROM
{ObjectQualifier_}PortalAlias INNER JOIN
{ObjectQualifier_}Portals ON
{ObjectQualifier_}PortalAlias.PortalID = {ObjectQualifier_}Portals.PortalID
*You need to replace {ObjectQualifier_} with the prefix used to create your site, if you did so, otherwise simply perform a find/replace and remove each {ObjectQualifier_} value. The purpose for doing this is to get the PortalID of the child portal of interest.
2) After making a note of your PortalID return to Host > Portals. You will either see an Export Template module in DNN v3.x, or a link with an arrow pointing left and a caption of "Export Portal Template" in DNN 4.x . From the Portal dropdown you will see all parent and child portals on your site. Select the portal of interest, your child portal, and enter a template name and description. Next, check the "Include Content" checkbox if you want the site content and click the Export Template link. This will create a new template file with your sites date that you will use when creating your new Parent portal.
3) Although you will not be able to export user information for those who have registerd, which is a nice safety feature, there is a module on snowcovered.com called "Bulk Import/Export", I believe, that will take care of this and also export your user's pwd (not encrypted either...). This was a huge help when I was upgrading from v3 to v4.
4) The next step is to create your new Portal. When adding the new portal you will see a drop down list that will have the name of all templates, including the one you just created. Use your newly created template and add all other necessary information required to create your portal. When done you will have a new parent portal with all your data (less the registered user information).
5) When you create your new portal make sure you have the PortalID, if possible. There should be a link, "Customize", next to the "Home Directory:" label on the Portal creation page. After clicking this link you will be able to entery "Portals/xxx", where xxx is the PortalID you noted. The DotNetNuke team saw the value in this so that we could specify our portal ids, and in your case, keeping non-relative links to information you just exported in tact. I've done this both ways and it wasn't a huge ordeal to modify my data so that it correctly pointing to the proper resource, but it's a neat feature that you might want to consider.
If you have a custom skin you will want to upload this to your new portal and apply it. You may need to move modules around to fix any layout issues, since a custom skin may have more containers than the default skin. Again, this is not a big issue.
Side Note: If you have a multi-portal DNN website and are running this on your own PC, WinXP, rather than a shared website, you will need to modify the record(s) in the PortalAlias table so that you can access your child portal. For example, if the website you setup locally is localhost/DotNetNuke4, then enter this value in the "HTTPAlias" column. You will need Enterprise Manager or Query analyzer to update this this table (using the Host > SQL module might be a bit dangerous to use for this purpose). When you have completed this you can run your site, i.e. http://localhost/DotNetNuke4, for example, and your child portal will show. Now you can export your child portal picking up with Step 2 above.
Hope this helps and good luck!