A few quick pointers for newbies running Windows.
Now to really do farming with Bitcoin you should setup custom linux distros to boot from flash drives preferably, of which there are many guides around the forums, but it is understandable to want a dual purpose machine now that the price has settled and for that most of you will want a windows box.
Advice #1:Get some Malware protection. Spybot won't cut it.
Since we are in this for the money (most of us) I suggest Microsoft Security Essentials, it is free and works well in conjunction with Malwarebytes.
You can either use Malwarebytes on a scheduled scan, or preferably buy a license for the realtime protection. Newegg often bundles OEM disks with motherboards and other components, so knock it out there if you can since the costs will be much cheaper.
Grab a copy of Peerblock 1.1 (or whatever newer version at the time of reading)
Peerblock is an excellent tool for local IP address banning, you can import custom blocklists from iblocklist.com
and the default spyware filters.
This can also be useful for gamers and P2P hounds.
Alternatively or in conjunction you can use the HOSTS file native to windows for blocking known bad IP's.
This can be done manually and you can find out how from a simple google search. http://winhelp2002.mvps.org/hosts.htm
A simple GUI for accomplishing this the easy way can be found here: http://www.sordum.com/?p=7593
In Chrome goto Options -> Under The Hood -> Content settings
#4Use a virtual machine for your wallet.
If you are adverse to linux and have a copy of Windows 7 Professional, you can install a free version of Windows XP as a Virtual machine called "XP Mode' http://www.microsoft.com/windows/virtual-pc/download.aspx
Setup this machine with the wallet application and then never use it to do anything other than access your wallet.