Ubuntu Networking :: 2 NICs Causing Very Slow DNS Lookups?

I'm running Ubuntu 11.04 and I'm really new to linux. My problem is that whenever I try to browse a site I notice the website loads very slowly because it takes a long time to do lookups. I installed Ubuntu with an onboard NIC and later switched to a PCI NIC (Dlink DGE-530T). Although I disabled the onboard NIC in the BIOS, it doesn't help. Could this conflict in configuration be a problem? My download rates are fine, its just lookups that take really long ( upto ~ 10 seconds). I know the PCI network card is fine because when I jump to Windows 7, lookups are normal again (~ 300ms). At first I thought about installing the sk98lin drivers for the PCI NIC but I saw a couple of places where people have mentioned that the skge driver that comes along with the kernel is better.

I have tried a system wide as well as Firefox disable of IPv6. Here is my /etc/udev/rules.d/70-persistent-net.rules
Code:
# PCI device 0x1186:0x4b01 (skge)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:24:01:14:eb:39", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x10de:0x0373 (forcedeth)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1e:8c:3e:19:ed", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
The interface I want to use according to the listing above is the one with the MAC - 00:24:01:14:eb:39.

I tried removing one of the entries in the file above and rebooting but it still didn't work. Here is a look at my /etc/network/interfaces
Code:
auto lo
iface lo inet loopback
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.1.10
gateway 192.168.1.1
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255