Thanks James & Mikiem, I take your advice.
I tried my own experience.
I have 2 same sources of file:
One is photo file (JPEG) from my Sony camera (5.1 mega pixel)
Another one is video file (VOB + IFO) form my Sony Handycam DVD-RW (0.9 mega pixel)
The photo file I copied directly from card reader and stored it into my hard disc.
The video file I copied it using Sony Picture Package software and converted it into MPEG2 file and stored it into my hard disc.
I used 2 different video editing software.
First, I used EMC 9 MyDVD videovawe and created video file (for photo & video) by using the following settings:
PAL, MPEG-1 for video CD
Video-Roxio MPEG-1, Video Encoder, 352X288, 25 fps,1.15mbs
Audio-Roxio MPEG-1, Audio Encoder, Stereo 44.10kHz, 16 bit, 224kbs
Then I used Ulead Video Studio 10 to create video file (for photo & video) from same source of file by using the following settings:
24bits, 352X288, 25fps, Frame-based, (Video CD PAL), 4.3
I compared all the movie clips I have created by playing them using WMP11. I noticed the movie clips created by Ulead Video Studio looked good, but the one created by EMC the image looked jerky every 2 seconds.
I went back again to MyDVD videowave, this time I changed to "Generic MPEG-1, normal quality" and created the movie clip again, but the image still looked jerky. I tried the 3rd time, this time I changed it to "Generic AVI" and the image looked good, there was no more jerky image. It seems that EMC9 is not so good in creating a VCD file (by the way, I couldn't select the DVD quality mode as the key was not there, missing? Was it supposed to be there?)