You can try camstudio, it is a screen capture software. If the frame/sec is not fast enough, I remember Microsoft has a SDK (Direct show or ?) for this screen capture. from Athena Solution (www.athena-solution.com)

Based on the assumption that you do GIS project. Q1: normally, the road name for GIS project does not from image, it is from vector map data, the map data format could be shape file (.shp) or some other format. If you really want to get the road name from image, you need do image processing. Q3: ArcGIS has a development SDK and you can uses in windows application, it supports C++, C# and so on. You can check on ESRI website. Q4: If you have map data and in vector format, you don't need convert to line and you just read from the file. If you want to exact the road from a image, then again, you have to use image processing. Hope it help. :) From Athena Solution (www.athena-solution.com)