Hi RBL,
In regard to the description, I'd like to confirm if the scenario is that you have installed Office 2013, Skype and SkyDrive, and you want to use them with Office 365.
If yes, you can use the current Office 2013 with Office 365. Moreover, the settings of Skype and SkyDrive will not be influenced. But I'd like to let you know that you cannot use SkyDrive to sync data to the SharePoint Online for Office 365. It's required to use the SkyDrive Pro sync client which can be installed within Office 2013, or you can install the standalone version via this link:
http://www.microsoft.com/en-US/download/details.aspx?id=39050.
For your reference:
Use my current Office desktop apps with Office 365
If there’s anything unclear, feel free to point it out.
Thanks,
Cherry Wang