I think maybe you can just not show the lines in question. (See WWI 20.3 Characters, words, punctuated words, unpunctuated words, lines, paragraphs.) Something like:
let file text be "[text of the file of notetaking]";
repeat with N running from 3 to the number of lines in file text:
say line N of file text.
Alternatively, you could try to replace the lines in question. (See WWI 20.8 Replacements.) Something like:
let file text be "[text of the file of notetaking]";
replace line 1 of file text with "";
replace line 2 of file text with "";
but that my leave some blank lines at the start of your notes display.