I don't know if this is any help because I use PSE 5.0 not 2.0
In 5.0 under Filter in the menu bar you will find Correct Camera Distortion. Once this opens there are sliders for Vertical and Horizontal perspective. The vertical slider will help if the building is leaning back or forward.
Well, the best way is to use the ruler tool to draw a straight line along a known straight edge, such as the horizon or one of the upright walls, then go to rotate image, choose arbitary and it should solve the angle to give you a straight photo. however, make sure you dont over do this, as it may just be a trick of the perspective. I think this is why architechtural photographers use Tilt & Shift lens to compensate for this kind of effect.
or maybe I am just making this up and confusing it for something else., its been a very long day.
Paint Shop Pro also has the same tool. Just line it up with something that should be straight and click. I've also been learning how to use the perspective correction tool, to correct for things not parallel that should be. That is a little trickier to do and it is taking me some time to get a feel for it.
HOwever doing the same thing in Lightroom is far easier, you just go into the crop tool, use the straighten tool and it does the rest for you, straightens AND crops the image to fit.. very time saving.
