If I use Ubuntu how much I have to pay for server software

All the software in the Ubuntu repository is free of cost. You can of course pay for 3rd party software but you don't have to pay for anything that comes directly from Ubuntu.

you can make your own hosting server with ubuntu, you'll have to pay only if you want Professional support from canonical, but if you do all on your own the cost for you is only a few hours(as much) on configurating the server, see this page for more info about ubuntu server edition :)
http://www.ubuntu.com/products/WhatIsUbuntu/serveredition

I hope this could help you ;)

Do I have to have any other software other than Ubuntu serve to host a web site on my won Desktop (AMD 64bit).

Do I have to have any other software other than Ubuntu serve to host a web site on my won Desktop (AMD 64bit).

Depending on what you want to host in your web page, you may need or not some other software.
Almost everything can be covered with software provided by Ubuntu.

Please, could you give more detail about what kind of web pages do you plan to host?

Web with some Educational information, files which cane be downloaded, photos, even users can submit some files which will be verified and published. Web with 8 to 10 email IDs (example:- <email address hidden> , <email address hidden> etc.)

With a mail reminders to the users when a fill is uploaded to web.

It is going to be more like an educational information for students.

I guess you will not need any additional software to host that web pages as it seems fairly standard.

If you have used the server Ubuntu cd for installation you should have a lot of needed software already loaded.

Thanks for u r answers and suggestions

Just now I downloaded Ubuntu server for AMD64bit can I use that one or I have to bye the CD only.
Is there any difference between the download and the CD versions and Utilities?

I guess you have downloaded server ISO file.
If you burn it as an image, you will have an exact copy of the original server CD.

I will write that .iso file to a cd by using Nero burner

vijay,
There is nothing at all you will need to purchase to run an Enterprise level web server from your home PC using Apache.
Even the commercial Linux OSes, such as RedHat EnterpriseL, do not offer any packages that you can not get freely. (Well, speaking specifically toward apache and the like). You are mostly paying for support when you purchase commercial Linux distributions.
You will definitely have everything you need with Ubuntu and open source solutions free.

Thank you very much for your suggestions and guidance.

You are most welcome.

Please close the question as solved please :)

what us the solution for the inability to install ubuntu 7.10 on windows 98 desktop pc. The software did not run, message rundll error appeared.

hubdigger13 you should start a new question about that because it isn't directly related to the actual question, anyway you should reboot your machine and boot from cd to start installation, and there's no way to install wubi on a w98 based installation :) i hope this should answer this non-related question :P.