HELP WITH TABLES IN WORD XP!

GRR! I have this .doc that is used as an electronic form and is all formated with a table. Since I didn’t create the document, I don’t know what methods were used. Every time I insert a row it shifts every two or three rows to the right. WHY? WHY? WHY? I’m so mad! Anywhoo, can anyone provide help or direct me to a good advanced table formatting resource? THANKS!