I suggest a free software you can get off the web which is called Virtualdub (there are many favors of this software, so if one does not work, try another one)
Also, I suggest you get Divx 5.0.3 or higher, it is a good format. But is costs $30.00 to use it without the spyware to create video files.
I have a 2200 XP CPU with 512 megs (DDR 333mhz) of ram and the 64mb 8500 DVD ATI All-in-Wonder video card.
When using Virtualdub to capture video I had a problem with frames dropping, I solved this problem by lowering the screen resolution to 800 by 600 pixels. Now I have no problems capturing video (and audio at 187 kbps) at the NTSC standard 29.97 frames per second at a resolution of 640 by 480 with a data rate of 7800 bits a second (100% quailty on a Divx '1 Pass Quailty Based' capture).