yea, I guessed as much 
Ok; everyone knows this part; just two wifi connections and both have Internet Service
Code:
Modem===Router - - wifi - - system#1 system#2
| ^
V |
+ - - - - - - - - - - - - - - - - - +
With both systems running and connected to the router, you should be able to ping on system#1; ping system#2's address
on system#2; ping system#1's address
here's the tricky addition
Code:
Modem===Router - - wifi - - [B]system#1---wired---system#2[/B]
| ^
V |
+ - - - - - - - - - - - - - - - - - +
Both wifi settings system#1 & #2 need the Gateway address to be that of the router. This you alread have if both have Internet Service.
All the wired stuff will need static assignments on both sides. I'll refer to the new setup for wired as System#x Nic2
(implying the wired connection. leave all wifi settings as-as).
I also assume your router is at 192.168.0.1 (correct me as needed)
First get the WiFi settings from system#1 using ipconfig /all and report
- IP Address. . . . . . . . . . . . . : 192.168.0.4
- Subnet Mask . . . . . . . . . . . : 255.255.255.0
- Default Gateway . . . . . . . . . : 192.168.0.1
- DHCP Server . . . . . . . . . . . : 192.168.0.1
- DNS Servers . . . . . . . . . . . . : 8.8.8.8
the above are used to seed the static settings.
For now, focus on the config, not the how-to
we config system#1 Nic#2 like
- IP Address. . . . . . . . . . . . . : 192.168.11.2
- Subnet Mask . . . . . . . . . . . : 255.255.255.0
- Default Gateway . . . . . . . . . : 192.168.11.4
- DHCP Server . . . . . . . . . . . : 192.168.0.1
- DNS Servers . . . . . . . . . . . . : 8.8.8.8
we config system#2 Nic#2 like
- IP Address. . . . . . . . . . . . . : 192.168.11.4
- Subnet Mask . . . . . . . . . . . : 255.255.255.0
- Default Gateway . . . . . . . . . : 192.168.11.2
- DHCP Server . . . . . . . . . . . : 192.168.0.1
- DNS Servers . . . . . . . . . . . . : 8.8.8.8
Notice the IP of one system is the gateway address in the other system.
to make sharing much easier, let's call system#1 Mickey and system#2 Donald
We add Mickey and Donald to the top of the
\windows\system32\drivers\etc\hosts file like
Code:
# this one will already exist
[COLOR="Gray"]127.0.0.1 localhost[/COLOR]
## you add these two
[COLOR="Teal"]192.168.11.2 mickey[/color]
[COLOR="Red"]192.168.11.4 donald[/color]
Obviously you can use anything you like other than mickey and donald 
to get the updated hosts file to be used, we need to bounce (stop/restart) like this
net stop "dns client"
net start "dns client"
and the quotes are required.
you should NOW be able to ping
Code:
on system#1; ping system#2's address
also ping donald
on system#2; ping system#1's address
also ping mickey
Once you can pind donald & mickey then \\donald\sharedDocs and \\mickey\\shareDocs will work.
DO NOT USE INTERNET CONNECTION SHARING! this will just mess up the whole thing.
Whatever firewall you are using, you enable Print/File Sharing on both systems.
If necessary, you can manually configure network access
Code:
allow in tcp/udp src-ip 192.168.11.* input-ports 137-139+445
allow out tcp/udp dst-ip 192.168.11.* output-ports 137-139+445
Whew! let's see how you stand on just understanding the above concepts - - - -