Welcome to Techzonez Nico, Hopefully you got it sorted out in time for your presentation... basically normal windows XP can be used for this... simply plug in your speakers and mic, then select Mic as recording input from speaker properties in control panel, and un-mute mic from play-back tabs... just make sure the speaker are not next to the mic - else you will get massive feedback screeching noise... so, in the end, I dont think you need 'special' software to do what you want...

hope it works... cheers.