I am trying to run Firestarter firewall but keep getting the message ETH0 is not ready.
This problem has been highlighted by others but is there a simple way of sorting this out, answers in other forums are wide and varied. but it's not clear if they have been successful.

Ignoring the firewall aspect, can you send any traffic over Eth0? And that is the interface that you are trying to use (rather than, say, Eth1, or Wlan0 or something)?

Sorry, I have no idea how to check that out as I am fairly new to Linux.
There is an option in Firestarter with Wlan0 but on that option it would not install.

Open up Terminal and type in the following:

Then press Enter. Please paste the information that follows in a post here so we can see what interface(s) you're actually using.

ifconfig
eth0 Link encap:Ethernet HWaddr 00:1a:92:7d:13:08
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:23 Base address:0xa000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:60 errors:0 dropped:0 overruns:0 frame:0
TX packets:60 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:4096 (4.0 KB) TX bytes:4096 (4.0 KB)

wlan0 Link encap:Ethernet HWaddr 94:44:52:4e:bf:39
inet addr:192.168.1.65 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::9644:52ff:fe4e:bf39/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:21771 errors:0 dropped:0 overruns:0 frame:0
TX packets:11352 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:13307465 (13.3 MB) TX bytes:1643981 (1.6 MB)

It would appear that wlan0 (wireless) is the active internet connection. That's the one to point Firestarter at.

I did a presentation on Firestarter for my LUG. If you'd like the handout, you can find it here:

http://www.pineviewfarm.net/misc/TWUUG_HO_FS.pdf

It is obvious form this that the interface that you are actually sending your data over is wlan0 (some local interprocess data is going over lo, but you can ignore that for the moment).

Is this what you are trying to do (ie, use the wireless connection, wlan0 for your connection to the outside world)? Or, is it the case that you are trying to use the wired connection eth0 for your connection? In the former case, you have to configure the firewall to use wlan0, in the latter case, you have to find out why you are getting the error message with eth0 (complete WAG: do you have a working driver for your ethernet card?).

Thanks, that has sorted it out (almost) It's up and running but I now get a message "failed to open the system log, No event information will be available"
If I try to reload it I get "error reading system log (null) file does not exist.
The firewall is running as I can see the outgoing address.
Any further thoughts on this.