Hi
I installed SP2 which knocked out my graphics card drivers and left me with a 640x480 4bit screen. Not very useful. It took two re-installations of my original Nvidia drivers to get back to normal.
Also, SP2 has a known problem with Nero Burning Rom which has already made available online a suite of downloads to rectify the problem. If you only have a dial-up connection you have a problem.
I am still using SP2 but I am waiting for more problems to arise.

Hope I'm wrong
Alan