The Dial Other Internet Providers program lets you setup accounts for different internet service providers. You can choose to use either SLIP or PPP (see the note about PPP below). This dialer program essentially acts primarily as a friendly GUI front-end to the text-based programs it calls (namely SLIP.EXE/PPP.EXE, SLATTACH.EXE, etc).
The dialer program in the IBM Internet Connection for OS/2 folder can only be used with Advantis. If you want to subscribe to other internet service providers, you need to use this dialer program instead.
Note about PPP: The dialer program as provided in the November 1994 release of OS/2 Warp does not include support for PPP. You need to download an update using the Retrieve Software Updates program.