6.
See this link for step by step instructions.
UT-300R2U ADSL MODEM MULTIUSER CONFIGURATION
DNS as given here.
or
7.
for screen shots
Check Post No 10 again.
The little I know about Dataone Broadband Services offered by BSNL
The link gives you correct settings for your modem.
8.
The diagnostics page you have posted shown no connection,
but you say you are connected. ( first five entries OK )
http://img542.imageshack.us/img542/6535/clipboard01wr.jpg
from my modem:
Test the connection to your Internet service provider
Test PPP server connection: PASS
Test authentication with ISP: PASS
Test the assigned IP address: PASS
Ping default gateway: PASS
Ping primary Domain Name Server: PASS
Also as mentioned earlier add DNS 8.8.8.8 and 8.8.4.4 in modem page.
9.
In computer :
There are two parts:
TCP/Ip properties
first one :
Obtain Ip adddress automatically.
Second Part : DNS
( IF entered in modem)
select obtain automatically
ELSE
enter 8.8.8.8 and 8.8.4.4
AppLY SAVE.
10.
Your ipconfig /all will show above dns.
copy/paste here.