By using the option ``-l'' you can specify the
type of header that should be displayed before each
single game in the output.
You have the choice between the styles "names", "nameselo" (the default), "siteevent" and "informator". To make the decision easier, why not taking a look at the examples?
If you say
pgn2ltx -l none < a.pgn > a.tex
no LaTeX header is output but only the game data, which can then be pasted into another text. Please, regard that you have to provide an appropriate header in this case.
If the supplied formats are not enough for you refer to the section Defining new headers, please.