Merging Polygons in ArcGIS 9.2 is easy. To combine two or more polygons into one using ArcView, all you need to do is the following:
>start editing with the editor toolbar...
>hold shift and select the polygons you would like to merge
>click the editor drop down menu on the editor toolbar
> select merge
>then select the polygon whos properties/attributes you would like the new polygon to preserve.
Then, you are done.