weirdo problem

hello all. i have problem with configuring network on centos. im using realtek 8191se on WIFI, centos got ip by himself, but when i want to ping router ip (192.168.1.1) it comes shit.

login as: root
Access denied
root@192.168.15.128's password:
Last login: Fri Nov 18 21:39:01 2011
[root@cabalserver ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:F7:BE:CD
inet addr:192.168.15.128 Bcast:192.168.15.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fef7:becd/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:81 errors:0 dropped:0 overruns:0 frame:0
TX packets:117 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:10733 (10.4 KiB) TX bytes:23704 (23.1 KiB)
Interrupt:67 Base address:0x2000

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:3313 errors:0 dropped:0 overruns:0 frame:0
TX packets:3313 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9165128 (8.7 MiB) TX bytes:9165128 (8.7 MiB)

[root@cabalserver ~]# ping -c4 192.168.15.128
PING 192.168.15.128 (192.168.15.128) 56(84) bytes of data.
64 bytes from 192.168.15.128: icmp_seq=1 ttl=64 time=0.073 ms
64 bytes from 192.168.15.128: icmp_seq=2 ttl=64 time=0.023 ms
64 bytes from 192.168.15.128: icmp_seq=3 ttl=64 time=0.024 ms
64 bytes from 192.168.15.128: icmp_seq=4 ttl=64 time=0.024 ms

--- 192.168.15.128 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3002ms
rtt min/avg/max/mdev = 0.023/0.036/0.073/0.021 ms
[root@cabalserver ~]# ping -c4 192.168.1.1
PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.

--- 192.168.1.1 ping statistics ---
4 packets transmitted, 0 received, 100% packet loss, time 3000ms

can some1 help me plz? ill be appreciate cuz bcz of that i have later problems with cabal_install.sh got many errors but mine error is cannot connect to centos bases - time limit is finished.
soz for my english but maybe sum1 will understand mine problem.
im GREEN at centos (using 5.6) if u know solution plz send it here and write it STEP BY STEP cuz im newbie :) ty a lot!