Disaster recovery options
Oracle, db and OEM installed on same host, archiveloging on, using OEM's Oracle suggested backups done daily using the flash recovery area. (No rman catalogs)
C:\ drive - OS, apps and oracle install
e:\ drive - Oracle's system db files, and flash recovry area
f:\ drive - Application specifc db files
g:\ drive - redologs
Using Symantec's backup exec - system recovery - we created a recovery image of c:\ drive after the db and OEM was setup.
We also use backup exec to archive f:\flash_recovery_ area to another host for offline/tape storage on a daily basis.