modem problems

[squareyes]

Hi all,
am having modem/dialup problems.
Set up my dial up connection with "system configuration
networking, and connected.last night OK. This morning Connection was 
extremely slow (0-1k/sec)
so deleted connection and set up wth pppconfig - result was as below 
when I connected.

$ pon optusnet
The file /etc/ppp/peers/optusnet does not exist. Please create it or use
a command line argument to use another file in the /etc/ppp/peers/ 
directory.
../
optusnet
ppp0
provider
wvdial
wvdial-pipe

It appears to be in there.
 
Checked pppconfig, there is only a connection  "optus.bak"

sudo pppconfig, removed optus.bak set up new,
create connection - provider - Dynamic DNS - pap - my login name - 
password - 115200 -
/dev/ttyS0(external modem) -write files etc. - exit -
tried pon optusnet

 connects, and drops out straight away.
Am connected with Knoppix at the moment, so doubt its the modem(ttyS0)

Any ideas what I am doing wrong. In the last few weeks have set up 
connection everytime I connect,
using knoppix, so could nearly do it in the dark :-)
Problems started Friday night, started apt-get update, aptget update, 
and my ISP
disconnected me at 5 hours disrupting the upgrade. Then on boot and 
opening gnome desktop I got message
"your session lasted less than 10 seconds etc, could be drive is full. 
27 gig drive so I didn't think so.
 I have done a complete re-install, and since then this is happening. I 
replaced the line to give access to hda1(windows partition in /etc/fstab 
(printed out fstab file prior to this ) , but system did not like it, 
showed errors during boot, changed it , have windows icon on desktop, 
but will only open it the first step, shows "auto exec.bat" etc, down to 
"windows", but will not go any further, and give access to "desktop" 
etc. Windows Icon does not show in "Desktop"(ubuntu) in the "Computer" list

If this should happen again, is there any way of recovering system, 
opened terminal with
Ctrl+Alt+F2 sudo bash dpkg --configure -a    no joy.
Thanks in advance,
Take Care
Winton