1. take cold backup or ur database
sql>shutdown immediate;
sql>rem using OS copy cmd COPY all datafile files, redo log files, control files , spfile, password files, No need to archive log files.transter ur backup to another machine.on another machine install oracle software without database.and fellow below procedure.
C:\>set oracle_sid=orclC:\>orapwd file=d:\oracle\product\10.1.0\db_2\database\pwdorcl.ora password=oracle
C:\>d:\oracle\product\10.1.0\db_2\bin\oradim.exe -new -sid ORCL -startmode manual -spfile
Instance created.
C:\>d:\oracle\product\10.1.0\db_2\bin\oradim.exe -edit -sid ORCL -startmode auto
C:\>sqlplus/nologSQL*Plus: Release 10.1.0.2.0 - Production on Sat Dec 9 12:36:53 2006Copyright (c) 1982, 2004, Oracle.  All rights reserved.
SQL> conn sys as sysdbaEnter 
password:
Connected to an idle instance.
note 1.paste all datafile , redo log file, control file, or spfile<sid>.ora in there location. 
create folder in oraclehome/admin---bdump 
or cdump 
or udump
and                            
oraclehome/ordata--orcl (according to ur dbname)
SQL> startup
ORACLE instance started.
Total System Global Area  171966464 bytes
Fixed Size                   787988 bytes
Variable Size             145488364 bytes
Database Buffers           25165824 bytes
Redo Buffers                 524288 bytes
Database mounted.Database altered.
SQL>