If you really want help then you should give the exact error message that you got when you tried it. Also you should not create a 2gb tablespace with a default initial extent of 1gb. When you try this what happens. Oh and is there any reason why you don't upgrade to 9i SR2 or 10g?
Code:
DROP TABLESPACE temp INCLUDING CONTENTS;
CREATE TABLESPACE TEMP
DATAFILE '/u03/oradata/F/TempF_01.dbf' SIZE 1950M REUSE
DEFAULT STORAGE ( INITIAL 1M NEXT 1M MINEXTENTS 1 MAXEXTENTS
121 PCTINCREASE 0 ) TEMPORARY;
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