[closed] OS OpenData, FWTools and ogr2ogr

I have previously used MapInfo to convert and extract portions of OS OpenData and open it in JOSM, my preferred online editor. It has recently come to my attention that there is an offset of three metres, approximately, due south when comparing my own file with other OS OpenData already uploaded. I have tried ogr2ogr through FWTools but obtain the message, "Unable to open datasource 'SU_Woodland.shp' with the following drivers.". It then lists ->ESRI Shapefile, ->MapInfo File and about another thirty such items. I have tried all sorts of different combinations without success. Typically, I am entering, "ogr2ogr -t_srs WGS84 -s_srs EPSG:27700 osm.shp SU_Woodland.shp" to convert SU_Woodland shapefile in OS projection to osm shapefile in WGS84. I should add that the four shapefiles, .dbf, .prj, .shp, .shx, are in the same folder as FWTools247.exe.

Solved! I am hopeless with DOS: the Command Prompt opens with C:Program FilesFWTools2.4.7>. Of course, I have to change the path to where the executable file resides!