I haven't read the thread but I would like to add (if it hasn't been said already)...
 
Upgrade to Sonar X3.
 
I had hard crashes with X1 and it was an absolute bear to use. X2 was a total glitchfest and still had some half baked features. X3 has been nothing but delightful and I'm still on the C patch and I have not changed a darned thing on my system. Little annoying my first experiences with Sonar weren't all that great but in the long run my initial instinct to go with X1 has proven to be a wise one.
 
Also I never would have come close to the skill level I have achieved in such a short time (although admittedly I still have a long way to go) without the support of the Cake community. I kind of disagree with the point Craig made about coming here for help. Sure you should explore all avenues independently and there is a certain level of white noise with all the various perspectives threads garner that can be a little daunting/distracting but more often than not, in my experience, someone will hit on the correct solution and even the answers that don't end up solving the problem tend to offer some more insight into the intricacies of the program, it's possible uses and computer based audio in general. Also, when everyone is getting along, it's a much nicer place to hang out than many other p2p forums... so that's nice.
 
It's been awesome having you functioning in a more official capacity, Mr. Anderton. Keep up the good work.

Kev999
 
Or, if you can't afford a separate PC or don't have the space to put it, then dual-boot is a good alternative.

I've been using a HD swap tray for years.  A stripped down install of Win7 with all network and non essential windows stuff shut off.
 
Paul

Dual booting using 2 separate drives is as good as having one pc just for music production and another for gaming.

When purchasing a PC research motherboards that have no known issues with audio production/streaming.

Only surf the net to trusted websites when running from your DAW drive, thus means there's no need for virus checkers or spam blockers or any fancy firewall other than what windows has built in.

Always create a restore point before installing any new hardware drivers. Many of the install processes will create a partial restore point. A manual one will be complete and will show in the restore list.   And a manual restore point before any big windows updates.
 
This is especially true for video drivers.
 
About monthly, and fur shur BEFORE AND AFTER big installs, create an image. I most often use an internal and copy to external. Much faster with an internal disk. Don't currently have a SATA port for external.  
 
Always create an image before any OS changes: 8, 8.1, 8.11,...
 
I will use the disk clean tool to get most of the debris. Then will open the user and windows temp folders and delete the remnants. Then move any downloaded files to be kept to the correct disk/folder.
 
I will stop the swap/page file, and hibernate function, reboot and verify the files are gone.
Some times I will defrag the disk. I use auslogics in optimize mode.
 
Create the image, and start the hibernate and swap functions.
 
And then, after the update is installed and working I will create a new image.