Need Stereo Mix feature with Vostro 1500 running WinXP

I mistakenly posted this topic in the Desktop forum, and am moving it here as my issue is with my laptop.

My Vostro 1500, purchased in 2008,  offers only 3 options for recording audio through the SigmaTel sound card:  Digital Mic, Microphone and Line In.  I am unable to record audio using Roxio Easy Audio Capture or any other audio recording software I have tried.  Through some on-line research, I have determined that my problem is that I'm lacking the Stereo Mix feature necessary for recording audio thorough the sound card.  The model of the sound card is SigmaTel High Definition Audio CODEC. I'm running WinXP Service Pack 2.

I am really unsure about downloading and installing drivers, but I have located a driver R171789 that I think might solve my Stereo Mix problem.  (https://support.dell.com/support/downloads/download.aspx?c=us&l=en&s=gen&releaseid=R171789&SystemID=LATITUDE%20PRECISION%20M65&servicetag=&os=WW1&osl=en&deviceid=8907&devlib=0&typecnt=0&vercnt=3&catid=-1&impid=-1&formatcnt=1&libid=3&fileid=235761)

However, before I proceed with the driver download, I would like to hear from someone with some knowledge on this topic who can tell me if that is the correct driver to use and if it has a history of working in my situation.  Any other advice you could give me on this topic would be greatly appreciated.