It might be your mpeg is not the standard VCD size (NTSC is 352 x 240).  You can use the TMPGEnc to re-encode the mpeg video but remember to set the video size to 352 x 240.  You can simply use the following procedures:
[File] -> [Project] -> Select Video-CD with [NTSC Film] -> follow the wizard settings to setect output filename.

請問各位大大:
怎麼把mpeg的檔燒成VCD的格式,我是用nero燒的,不過出來整個畫面變小了很多,這樣用電視看也不清楚,若有好方法,拜託各位大大傾囊相授了,感恩勒!