oracle hotbackup question .

zh57469

Hi,  i have a legato networker to backup all the db(oracle 10g) binary and data files , redolog, archive ( file system backup) to tapes everyday 2am while the database is still running , the db is running with archive mode , but no "BEGIN/END BACKUP "statements issued.
and i have a cold backup( db shutdown completely and OS cp command copy all the files to a remote NFS mount directories )  on every Saturday 7pm to 11pm . say the system crashed on Monday 10am , can i recover the db ? to which state( which day) ? is the legato networker 's backup file usable to recover the db ?