Software :: Stdio.h - File Missing During GCC Compile

I have looked at the other threads and found nothing which pertains to my issue. I am using an older version of Debian 4.0 I cannot upgrade until I have a 2nd server running. I lost the 4.0 installation disks. During an apt-get install i did, I foolishly changed sources.list to other sources on the net which changed dependencies and removed needed packages, such as perlmagick, Crypt-SSLeay, aptitude, and possibly the glibc - ( my current glibc was changed to glic6). Since I have found my original 4.0 disk. restored the sources.list. ran an update. and restored many of the packages that were removed. (a big lesson to me I will never do that again)

Here is a simple program:
#include <stdio.h>
When I run a gcc or I use cc compile
I get this message: "stdio.h": No such file or directory found.
Yes I know I missing the file stdio.h. I have looked
in /usr/include /usr/lib nothing.

Apparently during my mistake the system installed the glibc6 and removed the "stdio.h" file and other dependencies. I would like to get back to where as was in terms of the glibc version I had. Aptitude currently shows the following packages that are available to me

Code:
DEB1:/etc# aptitude search glibc
v glibc-2.3.6-2 -
v glibc-2.3.6.ds1-1 -
p glibc-doc
- GNU C Library: Documentation
v glibc-pic
p libg++2.8.1.3-glibc2.2
GNU C++ extension library - runtime version
p libstdc++2.10-glibc2.2
- The GNU stdc++ library
DEB1:/etc#

The question is which one should I install, to get my "stdio.h" back again? Would I have to uninstall glibc6 first? Uninstalling glibc6 displays a big warning. Is there a way I can download just the "stdio.h" files?