I have discussed the topic of when to backup your computer with lots of folks, most of whom never back up at all.  I also talk to people who use their computers as an electronic typewriter and rarely save a document after emailing or printing it.
 
I don't understand these people.  Having an archive of what I have sent and received is one of the most useful parts of computers for me.
 

I upgraded to Service Pack 1 when it was offered by automatic update.  I have my PC set to notify me when updates are available but let me choose to install them.  I usually check with Windows Secrets newsletter before I install an update.  Susan Bradley writes a great column on watching for good and bad and important patches.

My old laptop has been a great trooper these last 6 years, but 6 years seems long enough for a laptop.  Technology has moved on.  It was working OK, but some operations were getting slow, and I really couldn't upgrade all of the software.  In addition, as I support people in the AARP TaxAide program who are now upgrading to Vista laptops, I needed to learn enough about it to support them.  So I took the plunge to a new laptop.