I used a very easy username and password so it's not that. Please help, thanks.

Unlike Windows, Linux usernames are case sensitive (as well as the password, obviously); have you checked to make sure you are using the same capitalization as you did when you created the account?

Are you using the stock version of Linux that comes with the Eee? If so, it's specially mangled to be a single-user operating system. If you want full multi-user login, you have to take a number of steps - see here for a guide that I admit I never tried.

I spent some time working on the original version, trying to get it working as I wanted it. In the end, I decided it would be easier to install a different distro. My Eee is now running Debian Lenny quite happily.

You should still be able too use F9 reset to restore the system partition to factory settings, but that would, of course, wipe any changes you have made. You could also, of course, try booting from a live distro on a memory stick (Asus supply a utility to make a stick bootable) and make some changes to try to get the system to boot.

P.S. - by the way, the default user is called user.

Robhogg, thankyou very much. I've now sorted the problem thanks to your advice. Legend!