They say netbooks can't handle photo editing. I have a netbook as well, but I don't use it much anymore. I used to have photoshop on it, and never had a problem. The only problem I had was that the whole program didn't fit on my screen.

All I can say is, unistall the trial and reinstall. If that doesn't work, then well, it would be the fault of the netbook.

Perhaps the tutorial doesn't allow the blur tool? Either that or you've done something with the layers. Check that you're blurring on the layer you want to blur on and check the blur opacity.