Launch it from the terminal and read the error messages. Post the errors here so we can see if we can help you.

xboxrulz

I corrected the problem by downloading Firefox manually and manually moving the files over to /usr/lib/firefox.
Somehow that directory got deleted.

I had to do it via the terminal because I need to sign in as root user to access /usr directories. Is there a faster way to move files, like the old xcopy command in MS-DOS?

this is probably due to the fact that your ubuntu Linux did not start up properly. i'm pretty sure that the menu you choose in order to startup was something like "starting without network".
And the network settings were probably the reason why the desktop could not start properly.
I would suggest you to simply boot on the "Mandriva One" livecd, and see if it works correctly. Booting from a CD will last a little bit more, and you will have to answer some stupid questions like "english keyboard or not?" but you will see if all your screen and ethernet drivers are present and if the whole thing agrees with your way of thinking.
Booting from a liveCD is a way of testing Mandriva without installing it on your hard disk : if you like it you install it, if you don't like it simply forget about it. But the way I see you hating command line and security things tells me that you definitively should choose Mandriva.

I have tried Suse linux 10 which i find very usefull , but internet access is hit and miss. Maybe it is because i have a us robotics ADSL ROUTER/MODEM which only has windows drivers? i have an AMD dual core processor 64 bit. 1024mb ram

Why don't you try Freespire? It's based on Ubuntu, but has the same package system than Linspire, very easy to search and install packages.

Try typing this in the console: apt-get install firefox

If that won't work try apt-get install mozilla-firefox

I'm sure ubuntu has some graphical package manager, but I'm not quite familiar with Ubuntu. I think it's called Synaptic. Anyway, if the first two commands won't work just try looking around in Synaptic.

As for the server, I think it'd be worth it to learn some basic commands and get one up and running without a graphical interface. Heck, you might be able to set one up just by following a few online guides.

Here are a few distros you might want to give a try (for the server): debian, slackware or fedora core. (or you could go with FreeBSD, I'm sure it has some easy online guides that'll let you set up your own server)

I recommend PCLinuxOS, it's free, easy, and it is loaded down with features. It has that previously mentioned graphical package manager, Synaptic. It also comes with Firefox pre-installed. I would be using it right now, but my laptop hates Linux

Don't worry the problem is solved now. I am enjoying Linux quite a bit and learning command line stuff bit by bit slowly.

Anyone recommend anything with graphics on the old Windows 98 machine?

Usually the old Windows 98 machines are small machines with very few memory, so almost only windows 98 can run on them.

I have 64 MB RAM on the Windows 98 machine, not enough for Ubuntu. I don't have Internet access whatsoever on that machine also, I can only rely on floppy disks and CDs. I need a good version of Linux though, for server development purposes if possible.