If i can get it to work in my i5100, I promise you're i5150 is capable ...  connect the s-video cable and then try right clicking the desktop and clicking properties ... click the settings tab and then advanced and see what you can find that deals with two display sources (sorry I can't give you exact info but I'm not at home right now)

Please note you must have connected the svideo cable to the laptop prior to boot up...or else the video driver will not alow for svideo out as an option

My old toshiba had a geforce2go in it and i don't remember the process being that much different that one it is now ... most video drivers are fairly intuitive in that respect

Follow the steps below... got 'em from Marty..

Note: All relevant audio/video cables and equipment should be turned on and connected to the laptop before starting these steps. You may wish to reboot the computer after connecting all cables. Do this first then repeat the steps below if you are not initially successful with the forthcoming instructions.
1. Right click your dektop and click "properties"
2. Click "settings" -> "advanced" -> "nview" or "GeForce"
3. Move the dot from "standard" to "clone" (if you cant see it, click on display properties on the left hand side menu).
4. In the drop down menu, select "tv monitor" (or whatever entry corresponds to a tv, I'm writing these directions from memory)
5. Place a checkmark next to "Make this the primary display".
6. Click "ok"
7. Windows will ask you to confirm these settings, tell it "yes" or "ok"
8. You should now see your desktop on the tv. If the desktop is too big for your tv and thus scrolls or shifts when you move the mouse, you may wish to decrease your resolution to 1024x768 or 800x600 (the resolution can be changed under the "settings" tab referenced in the above "step 2"). Do this if you cannot fit the entire dvd image on your tv.