You can't capture analog with Vidcap. I use iuVCR from www.iulabs.com. It's a GREAT capture program and it has more features that almost any other vid capture utility i've seen.
Actually SonicFoundry's VidCap will let you capture analog if it can access the drivers for your analog capture card. Under the Video menu select your video source. The video menu will now change to list Capture Properties and Capture Capture Properties for the device. Each of these options accesses some but not all of the features of the device. You may be able to do some YUV type of color compression, but usually that's about it. You'll mostly likely be limited to capturing to AVI.
My standard method of capture is through an Osprey analog card. Works a treat through VV3 - in fact it's more stable that way than through the card's dedicated capture app.