my question is closely related to:

• How do I connect Ubuntu 10.04 and Windows 7 with an Ethernet cable?

What I am after is:

  Windows 7-------wireless-----\ 

                            Wifi router

  Ubuntu 10.04----wireless-----/

  Windows 7-------wireless-----\ 
      |
   cross_over_cable             Wifi router
      |
  Ubuntu 10.04----wireless-----/

What I did was

On Windows edit

 system32\drivers\etc\hosts

Add the following line:

192.168.253.2 my_ubuntu_computer_name_&-wired   //?not sure if this is right

On Ubuntu:

sudo gedit /etc/hosts

Add the following line:

192.168.253.1 my_pc_computer_name&-wired //?not sure if this is right

and then Ubuntu 12.04 as the host

• Right click on the Network Manager applet, click Edit Connections...
• In the Wired tab, click Auto eth0, then click Edit...
• In the IPv4 Settings tab, change Method: to Shared to other computers.
• Click Apply and enter your password when it asks you.
• Close everything and reboot.
• Plug the Ethernet cable into both computers.

But,

• I can connect to my windows network folders from ubuntu via wifi
• I can't connect to my ubuntu network folders from windows via wifi(in fact this bit was working before - so my wifi connection is worse)

my ubuntu Auto Ethernet seems to be on

From Ubuntu

eth0      Link encap:Ethernet  HWaddr 00:11:2f:f3:43:8d  
          inet addr:10.42.0.1  Bcast:10.42.0.255  Mask:255.255.255.0
          inet6 addr: fe80::211:2fff:fef3:438d/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:172 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:27279 (27.2 KB)
          Interrupt:19 Base address:0xe400 

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:1147 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1147 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:94380 (94.3 KB)  TX bytes:94380 (94.3 KB)

wlan0     Link encap:Ethernet  HWaddr 00:03:c9:e9:6f:bf  
          inet addr:10.1.1.7  Bcast:10.1.1.255  Mask:255.255.255.0
          inet6 addr: fe80::203:c9ff:fee9:6fbf/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:13186 errors:0 dropped:0 overruns:0 frame:0
          TX packets:12187 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1598882 (1.5 MB)  TX bytes:1189555 (1.1 MB)

From Windows:

Windows IP Configuration

Ethernet adapter Bluetooth Network Connection:
   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :
Wireless LAN adapter Wireless Network Connection:
   Connection-specific DNS Suffix  . : BoB
   Link-local IPv6 Address . . . . . : fe80::ecf7:c445:3725:b9c1%12
   IPv4 Address. . . . . . . . . . . : 10.1.1.4
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 10.1.1.1

Tunnel adapter Local Area Connection* 15:
   Connection-specific DNS Suffix  . :
   IPv6 Address. . . . . . . . . . . : 2001:0:4137:9e76:1423:3ae3:f5fe:fefb
   Link-local IPv6 Address . . . . . : fe80::1423:3ae3:f5fe:fefb%23
   Default Gateway . . . . . . . . . : ::

Tunnel adapter isatap.BoB:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . : BoB

Tunnel adapter isatap.{D0C8EBA1-335D-4620-8570-6C36E8786D72}:

   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :