Wired Network not working on Ubuntu 11.10 + Strange Behavior with Manual Conf [closed]

Question

I'm new to Ubuntu - to be honest this is my very first day trying it... and I've already spent hours trying to make my wired connection work.

I've been using this wired network with Windows and OSX, and in both systems I also had some trouble trying to connect in the past (and the troubleshooters did their magic and helped me get connected).

Today, this is what I got:

I'm running Ubuntu 11.10;

ifconfig:

eth0      Link encap:Ethernet  HWaddr 78:2b:cb:c3:bf:8f  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:1 errors:0 dropped:0 overruns:0 frame:0
          TX packets:343 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:70 (70.0 B)  TX bytes:63273 (63.2 KB)
          Interrupt:20 Memory:e2e00000-e2e20000 

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:1859 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1859 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:149368 (149.3 KB)  TX bytes:149368 (149.3 KB)

wlan0     Link encap:Ethernet  HWaddr 10:0b:a9:82:55:c0  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:15484 errors:0 dropped:0 overruns:0 frame:0
          TX packets:16871 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:12048377 (12.0 MB)  TX bytes:2677679 (2.6 MB)

I also have some information from Windows ipconfig /all that I ran at my friend's machine

Ipv6 Address:    <address> preferential
Ipv4 Address:    172.26.65.23 <preferential>
Netmask:         255.255.254.0
Default Gateway: 172.26.64.1
DHCP Server    : <address>
DNS Servers    : <address>
DNS Suffix     : <suffix>

The weird thing is that I've tried to configure everything manually, using "Network Connections". When I add everything inside IPv4 Settings, the connection is finally successful, but only for 4~5 seconds before getting disconnected again...

Update:I just changed the Connection Method to "Local-Link Only", and the same described above happens: At first, it says "Connection Stablished", but after a few seconds, the wired network gets disconnected.

I hope someone can help me get connected!

Thanks!