You should really just be able to do startx to get to KDE, then open KPackage, and install the compiler package.
I don't use Redhat, but I think Redhat uses the rpm's and/or invented them.
The KPackage works on many distributions.
Obviously, you cannot compile a compiler without first having the binary installed. At a shell prompt:
gcc -v
should tell you if you have a compiler installed.
In KDE, far left taskbar should be K with orange gears, click and then select System, KPackage and click.
There are many files that need to be installed to run gcc, not just gcc itself. If you have package tool, it will tell you all the files needed, unfortunately, I don't think KPackage or rpm will tell you what entire package to install. In most Linux distributions, you can type pkgtool at the command prompt and select view installed packages. This will tell you what is in a specific package. Most packages run from /a to /yp, with the C and C++ stuff being in the /d package. Although you might think this is all you would need, you'd most likely be wrong. The shared libraries for glibc are in the /a package and a lot of editing stuff is in the gnome package, which is why it is better to do the full install early on. On at least one server. It doesn't matter if you're an FQDN or not, even for experiments, it's better to have everything on hand from the beginning.
The entire Linux install is around 3 gig, and recommended for FQDN servers. This way, everything is there before you need it, but you will probably need a Linux partition of at least 8 gig to handle it all.
I would probably prefer something like 20 gig or even 30 gig for that first Linux native server partition.
You're also getting C, C++, and probably g++ mixed up; you need the entire compiler packages from /a , /d, and I think /gnome, to cross-compile, which is what you're trying to do. Compiling today is almost always cross-compiling. Here's a clue: you need gcc-3.3.4 for gcc-g++-3.3.4 so that C++ can go back and compile C.
So, in the end, I think you're not installing all the necessary packages.
Check your installation of Redhat guide, etc..
You should be able to add the named packages with any of the tools referenced above; rpm [slow, but works], pkgtool [works probably best of all], KPackage [weird operation, as in uses "Open" to install a package and can do unexpected installs/uninstalls if you're not careful, but works nonetheless].
And if you use pkgtool, don't get impatient, it will take a few minutes for it to build a list of packages, just wait til it's done before giving up on it.
Notice that I'm using gcc-3.3.4, it came with the Slackware distritribution. I'll try Redhat again, someday.