Check with the EeeUser forum to see what they have to say.
http://forum.eeeuser.com/

I can't see trying to install a 2011 browser in a 2007 operating system. I replaced Xandros with Easy Peasy 1.6 a while ago, 3.0 & 3.5 were too damn slow on Xandros even with the GTK update. A 900MHx processor will never be a speed demon, but you gotta give it a chance with a better OS than Xandros. Personally, I am staying with 3.6.x until support ends. I don't see the need to update to the latest version of Firefox right now, especially on Linux.
http://www.geteasypeasy.com/

thank you the-edmeister for your detailed reply - you seem to have a vast amount of knowledge on installing various programs on the computer - is this your field of expertise? i did try to intall easy peasy, but it asks me what to do with it - same as with firefox 3.0 and i would need some other easy instructions to do it from the console - that you advised and worked perfectly so easy peasy is meant mostly to improve the speed on my computer thanks very much, once again

Nope, I am not a computer professional. I am retired from a different field, just been using computers since 1984 and learning as I go along. Unfortunately, I have only installed a new operating system on my EeePC once and I don't have the knowledge to give you any specific instructions.

Here are the brief instructions for installing EasyPeasy.
http://www.geteasypeasy.com/get-easypeasy
If you have questions, it would be best to ask in the Easy Peasy forums and be patient for a reply because that forum seems to be very slow these days. Unless everyone is using an alternative form of communication for help??
http://edge.geteasypeasy.com/help/

thanks i will keep that in mind appreciate your help

Please click the Solved It button next to the answer that answered or solved your Firefox support issue, it appears when you are logged in, so this thread gets marked as Solved to help other users who may have this same problem.

thanks, but nothing has solved it yet, until i go into the easy peasy forum and see what they have to say and i don't have time for it now i have upgraded to firefox 3.0 from your simple mode instructions in a reply you gave to someone else and it worked, so i am sticking with it for now thanks

I used these steps to install Firefox 6.0 on my eeepc (I've got Xandros on mine): 1. Close Firefox. Nothing else should be open.

2. Hold <Ctrl> and <Alt> and press the <T> key to open a Terminal / Console, and enter the following command:

sudo bash install_firefox.sh

5. Wait until done (at this point you will have installed Firefox version 3.0.1; you can continue now to install the very latest version)

6. Again in the Terminal / Console, enter

sudo firefox

7. Once in Firefox, select Help »> Check for Updates…

8. After everything is done. Close Firefox and the terminal window.

9. Now, you'll have the 3.0.1 version on your pc. I checked for updates till my Firefox gets the version 6.0. It worked fine.

Sorry my bad English! I hope it helps you. Good luck!