I have VMware that has a Windows guest OS I use with it. I found pulling files from the host (my base Kubuntu OS installed onto the "bare metal" of the computer) to the guest OS (Windows) using networking was extremely slow; a transfer rate of about 3KB/sec (slower then dial-up).
I found the answer in this thread.
http://www.vmware.com/community/message.jspa?messageID=360751
What this is saying you need to turn off TCP Segment Offloading or TSO. I am unsure if you need to turn if off for both guest and host, but I did.
To turn it off on the host (Kubuntu) I simply apt-get install ethtool and then ran:
sudo ethtool -K eth0 tso off
And then in Windows I went to the device manager and found the VMware NIC, openned it up. Went to Advanced and turned off TsoEnable by giving it a value of 0
All done. Thanks "cripy" from WMTN!