Windows 7 crashes while browsing then restarts on its own.?

Computer will shut down when browsing the web then restart on its own. This started about 6 months ago, just once in a while, but seems to be more frequent now. Any ideas on what my problem is? My event log for two days is listed below. Can anyone give me some suggestions on why my computer is showing all of these errors?

Tthanks,
Alan

OS- Windows 7 64 bit
Inspiron 560
Intel (R) core 2 quad cpu
6 GB
Firefox browser
Thunder bird-email
AVG anti virus


Warning 12/28/2011 7:37:49 AM SharedAccess_NAT 34005 None
Warning 12/28/2011 7:37:43 AM Wininit 11 None
Warning 12/28/2011 7:37:30 AM RTL8167 1 None
Warning 12/27/2011 9:31:18 PM WLAN-AutoConfig 4001 None
Warning 12/27/2011 9:25:37 PM RTL8167 1 None
Error 12/27/2011 7:05:18 PM Service Control Manager 7023 None
Warning 12/27/2011 7:03:20 PM SharedAccess_NAT 34005 None
Warning 12/27/2011 7:03:14 PM Wininit 11 None
Warning 12/27/2011 7:02:51 PM RTL8167 1 None
Warning 12/27/2011 6:57:17 PM WLAN-AutoConfig 4001 None
Error 12/27/2011 6:44:56 PM Service Control Manager 7023 None
Warning 12/27/2011 6:42:55 PM SharedAccess_NAT 34005 None
Warning 12/27/2011 6:42:25 PM Wininit 11 None
Warning 12/27/2011 6:42:11 PM RTL8167 1 None
Critical 12/27/2011 6:42:08 PM Kernel-Power 41 (63)
Error 12/27/2011 6:42:16 PM EventLog 6008 None
Warning 12/27/2011 6:26:48 PM DNS Client Events 1014 None
Error 12/27/2011 6:18:20 PM Service Control Manager 7023 None
Warning 12/27/2011 6:16:20 PM SharedAccess_NAT 34005 None
Warning 12/27/2011 6:16:04 PM Wininit 11 None
Warning 12/27/2011 6:15:50 PM RTL8167 1 None
Warning 12/27/2011 4:12:41 PM WLAN-AutoConfig 4001 None
Warning 12/27/2011 4:12:38 PM User Profile Service 1530 None
Warning 12/27/2011 4:02:01 PM RTL8167 1 None
Error 12/27/2011 1:28:57 PM PrintService 808 Initializing
Error 12/27/2011 1:28:57 PM PrintService 808 Initializing
Error 12/27/2011 1:09:53 PM PrintService 808 Initializing
Error 12/27/2011 1:09:53 PM PrintService 808 Initializing
Warning 12/27/2011 1:01:32 PM DNS Client Events 1014 None
Error 12/27/2011 12:27:10 PM PrintService 808 Initializing
Error 12/27/2011 12:27:10 PM PrintService 808 Initializing
Error 12/27/2011 12:03:30 PM Service Control Manager 7023 None
Warning 12/27/2011 12:01:29 PM SharedAccess_NAT 34005 None
Warning 12/27/2011 12:01:16 PM Wininit 11 None
Warning 12/27/2011 12:01:03 PM RTL8167 1 None
Warning 12/27/2011 12:00:30 PM Winlogon 6000 None
Warning 12/27/2011 12:00:29 PM Winlogon 6000 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:39 AM DistributedCOM 10005 None
Error 12/27/2011 11:56:39 AM DistributedCOM 10005 None
Error 12/27/2011 11:56:38 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:38 AM DistributedCOM 10005 None
Error 12/27/2011 11:56:38 AM DistributedCOM 10005 None
Error 12/27/2011 11:56:37 AM DistributedCOM 10005 None
Warning 12/27/2011 11:56:33 AM Wininit 11 None
Error 12/27/2011 11:56:31 AM DistributedCOM 10005 None
Warning 12/27/2011 11:56:30 AM Winlogon 6000 None
Error 12/27/2011 11:56:27 AM Service Control Manager 7026 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:25 AM Service Control Manager 7001 None
Error 12/27/2011 11:56:28 AM Eventlog 1101 Event processing
Critical 12/27/2011 11:56:16 AM Kernel-Power 41 (63)
Error 12/27/2011 11:56:24 AM EventLog 6008 None
Error 12/27/2011 11:22:08 AM PrintService 808 Initializing
Error 12/27/2011 11:22:08 AM PrintService 808 Initializing
Warning 12/27/2011 10:53:04 AM RTL8167 1 None
Error 12/27/2011 9:53:42 AM Disk 11 None
Error 12/27/2011 9:53:10 AM PrintService 808 Initializing
Error 12/27/2011 9:53:10 AM PrintService 808 Initializing
Warning 12/27/2011 9:49:20 AM RTL8167 1 None
Warning 12/27/2011 8:59:48 AM DNS Client Events 1014 None
Error 12/27/2011 8:39:11 AM SideBySide 63 None
Error 12/27/2011 7:30:06 AM Service Control Manager 7023 None
Warning 12/27/2011 7:28:01 AM SharedAccess_NAT 34005 None
Warning 12/27/2011 7:27:46 AM Wininit 11 None
Warning 12/27/2011 7:27:32 AM RTL8167 1 None

Most of the errors point at your NIC or the NIC drivers.
Try updating your NIC drivers and if that does not rersolve your problem I would try a new NIC.