Video playback help needed

OK you PC gurus, I need your help. I posted in case others may have a similar problem. I'm missing out on all these wonderful TKP analyses because the video clips are basically not viewable for me...they just play back in jumpy clumps rather than as a smooth fluid flow. I'm surfing on an antique laptop: Dell Latitude D600 laptop, Pentium M 1600Mhz, maxed out with 2GB ram, XP sp3, 32MB ATI MOBILITY RADEON 9000 video adapter, DirectX 9.0c, Broadcom 570x Gigabit Integrated Controller. I got laid off months ago and can't justify springing for a newer PC right now. I've searched the web but found no suitable answers. Is there a setting to force videos to be fully downloaded before playback begins? What I'm finding is that the video provider controls autoplay...that control isn't built into Flashplayer or Youtube. Any suggestions?