Slow query on OS X box

I have a table that contains over 13 million rows.  This query takes an
extremely long time to return.  I've vacuum full, analyzed, and re-indexed
the table. Still the results are the same.  Any ideas?
TIA
Patrick

mdc_oz=# explain analyze select wizard from search_log where wizard
='Keyword' and sdate between '2002-12-01' and '2003-01-15';
                                                         QUERY PLAN

-----------------------------------------------------------------------------------------------------------------------------
 Seq Scan on search_log  (cost=0.00..609015.34 rows=3305729 width=10)
(actual time=99833.83..162951.25 rows=3280573 loops=1)
   Filter: ((wizard = 'Keyword'::character varying) AND (sdate >
= '2002-12-01'::date) AND (sdate <= '2003-01-15'::date))
 Total runtime: 174713.25 msec
(3 rows)

My box I'm running PG on:
Dual 500 Mac OS X
1g  ram
Pg 7.3.0

Conf settings
max_connections = 200
shared_buffers = 15200
#max_fsm_relations = 100        # min 10, fsm is free space map, ~40 bytes
#max_fsm_pages = 10000          # min 1000, fsm is free space map, ~6 bytes
#max_locks_per_transaction = 64 # min 10
#wal_buffers = 8                # min 4, typically 8KB each




CREATE TABLE public.search_log (
  wizard varchar(50) NOT NULL,
  sub_wizard varchar(50),
  timestamp varchar(75),
  department int4,
  gender varchar(25),
  occasion varchar(50),
  age varchar(25),
  product_type varchar(2000),
  price_range varchar(1000),
  brand varchar(2000),
  keyword varchar(1000),
  result_count int4,
  html_count int4,
  fragrance_type varchar(50),
  frag_type varchar(50),
  frag_gender char(1),
  trip_length varchar(25),
  carry_on varchar(25),
  suiter varchar(25),
  expandable varchar(25),
  wheels varchar(25),
  style varchar(1000),
  heel_type varchar(25),
  option varchar(50),
  metal varchar(255),
  gem varchar(255),
  bra_size varchar(25),
  feature1 varchar(50),
  feature2 varchar(50),
  feature3 varchar(50),
  sdate date,
  stimestamp timestamptz,
  file_name text
) WITH OIDS;

CREATE INDEX date_idx ON search_log USING btree (sdate);
CREATE INDEX slog_wizard_idx ON search_log USING btree (wizard);