Remote Desktop Running Slow on Windows 8

I have just purchased an Acer Aspire M laptop running Windows 8 and I have setup my VPN for the office so that I can remote in and access my work pc. Having done this previously on a laptop running XP, Vista and Windows 7 I thought this would be straight forward in Windows 8. However, having set everything up when I connect to my work pc the response time is agonisingly slow, why is this? What I have also noticed is that when you login with the older operating systems the desktop of my work pc is blacked out whilst on Windows 8 the image that is on my desktop is there to see (not blacked out) could this be a reason for the delay. Any help would be greatly appreciated as I have spent some cash on this laptop and at the minute it's performing worse than my old, old XP laptop.