If your computer savvy enough and willing to pay the price and buy a copy of Virtual PC or VMware then you can have some fun with all this. Here's what I use for browsing when I suspect there may/will be some problems. I also use it for forensics work when there are "delicate" client issues involved and I want absolute security. 70-80% of my computer usage now is inside a VM.
I use VMware but Virtual PC works equally well and is cheaper. Both allow you to create a virtual PC and load any operating system into it that will run on an Intel processor. I loaded Windows XP into a VM. After setting it up, I activated it with Microsoft, tuned it to look and feel the way I wanted it then set the virtual machine to what's called "non-persistent mode" (I'll explain later).
Now I can boot my Win2K machine, a Micron 2.5ghz laptop and start VMware which loads Windows XP. I can run XP in a window or full screen. Now I go do all the browsing, downloading, opening of attachments or any other dangerous behavior. If the machine is infected, pirated, blown away or whatever I just reboot the WinXP VM (a mouse click on the host).
When the VM-WinXP reboots, it discards all changes made to the VM and it's back to the same state as it was when I set it in "Non-Persistent" mode. In other words, every change made to the WinXP VM is gone, every virus, trojan or whatever and it's back to as installed.
A virtual machine is just a folder on the host C: drive but to the VM it looks like its own C: drive. The VM folder can be copied to another machine (it's just a folder, after all) that is completely different from the system it was created on and it will work perfectly.
The reason for that is that VMware and Virtual PC both "virtualize" the hardware creating a hardware abstract layer, the OS in the VM always see's the exact same hardware configuration regardless of what machine it's on.
It's a lot of fun to see exactly what a particular virus or trojan will do, how it works and what countermeasures work best. A VM is the perfect platform for that.
VMware and Virtual PC are very similar in functionality with the edge going to VMware overall. VMware though costs about three times what Virtual PC does.
This stuff's a real gas to play with. Want to run Linux?, do it in a VM. How about old Windows 3.1, Win98, Win95, DOS and all it's various flavors, remember DRDOS (it came from the old CP/M world, and yes, I was even able to load OS/2 Warp, all in a VM, created by VMware running under Win2k on a laptop.
I also use it to test server platforms and configurations. I've loaded Novell NetWare 4.11, 501 and 6.3. All three come up with no problem. The same for WinNT, Win2k, Win2k server, advanced server and datacenter edition, all in VM's. All of them look and perform exactly the same as a real, physical server, all of them hardware abstracted, all portable between physical machines. I can even run several different OS's at the same time on my laptop, subject to performance limitations of course.
The difference between "Persistent" and "Non-Persistent" mode is whether or not changes made to the VM during operation stick. In persistent mode they do, exactly like a real system. In non-persistent mode all changes made to the VM during operation are discarded when the VM is shutdown or rebooted. And yes, before you ask, you can switch the Non-Persistent mode on and off at need.
Al