Automatically?  I doubt if you can install a service using the user's account 
without supplying the user's password.  I've honestly never seen a Windows 
application installer attempt to install a service using a user account.  Leave 
it up to the user to do this if desired, or perhaps prompt the user during the 
installation.  

Windows XP and Win2k3 Server have several predefined accounts for services that 
need local network access.  This won't give you access to a particular user's 
mapped network drives, but I believe they will permit the SlimServer service to 
use UNC style network shares.  And they have no password.

http://msdn.microsoft.com/library/default.asp?url=/library/en-
us/dllproc/base/localservice_account.asp

http://msdn.microsoft.com/library/default.asp?url=/library/en-
us/dllproc/base/networkservice_account.asp

Prompting the user would be fine, if necessary.  Basically, this should run with the user's access to their 
own music, which is the root of the problem.  Mapped drives are a common problem (our most 
frequently asked question.)

cc'ing vidur, who understands all things windows.

Install can specify a user name and password.  Details here: 

http://ASPN.ActiveState.com/ASPN/docs/PDK/6.0/PerlSvc_overview.html

Alas, not going to make it for 6.2.1.  

Ping

This is an unusual case and if someone knows enough about services to want to do this, they can do it manually.