Creating a table with spatial data is done using the "CREATE TABLE" SQL command as normal, declaring the spatial columns as type "geometry". Note that:
There is no distinction between points, lines and polygons at the SQL datatype level. All GIS objects are declared as "geometry", no matter when their underlying topology. This means that you can have points, lines, and polygons all sharing the same spatial column of a database table. If you are making assumptions about feature type homogeneity, you will have to enforce them at the time of data loading or retrieval, the database will not do it for you.
Unlike some commercial spatial databases, there is no limitation on the number of spatial columns you can put in a table.
"Geometry" is a reserved word now (it is the GIS datatype) so you cannot name your spatial column "geometry". Try "geom" or "parks" or "frank".
Here are some examples of "CREATE TABLE" commands using the "geometry" type:
CREATE TABLE bc_parks ( PID int4, PIN int4, PARK_NAME varchar(80), PARK_DATE date, PARK_GEOM geometry)
CREATE TABLE road_segments ( GID int4, GEOM geometry, SURFACE varchar(20), NUM_LANES int2)