Mystery Flights

Using XP and FS2004 my programming seems has gone a little crazy. I usually take off from Seattle International and often fly to Vancouver international. Just recently, after commencing to take off the aircraft pulls sharply to the left. The buildings which are usually to the right of the runway now appear on the left. With some fairly determined leverage I can sometimes get airborne depending on the aircraft but usually just veer sharply to the left before going into a spin if I persist.
I recent installed FS Passenger and the uninstalled to see if it made a difference, it did not. I dont think crosswind is the problem. I can easily uninstall FS2004 and reinstall but before I do I thought I would ask first.
Thanks in advance.

I think maybe its a hardware problem. And about the buildings thing, you probably started from 34R or 34L(which will show buildings to the right side of the plane), and now you start at runway 16L or 16R(shows the buildings left side of the plane)

thanks.
I just discovered that I had not returned FS2004 disc 4 to the drive. That was the problem.