Speakers/Headset

I am using an old Soundblaster card on my PC. There is only one plug for outline. I use Skype and Messanger for Internet calls. I keep my speakers hooked to this outline so I can hear the "ring" - and once I answer - I take out the speakers - and hhok up the earphone - for privacy.

Any solutions? Do I need to go to a better Soundcard? Can this be controlled via software? (My speakers do not have a plug for earphones).

Thanks