Easy enough with sed:
sed -n 123,230p filenameThis will output filename content, from line 123 to line 230, inclusives. Notice the p letter after the last line number, this is what instruct sed to print to stdout.
A tip when working with large files: Add ;231q after 230p, to prevent sed to keep scanning until EOF (end of file). The whole command would then be:
sed -n '123,230p;231q' filename