apt-get install kernel-image-2.4-686 (or replace 686 with yer architecture if there's something different.)
It is a virtual package, which Debian says: This package will always depend on the latest 2.4 kernel image available for Pentium Pro/Celeron/Pentium II/Pentium III/Pentium IV.
This way, by running apt-get update and apt-get upgrade religiously, you will be notified as soon as a new kernel is available.
He also points out Emacs Anti-News, which begins:
For those users who live backwards in time, here is information about downgrading to Emacs version 20. We hope you will enjoy the greater simplicity that results from the absence of many Emacs 21 features.
...The arrangement of menu bar items differs from most other GUI programs. We think that uniformity of look-and-feel is boring, and that Emacs' unique features require its unique menu-bar configuration.