H ipkmishra86, You will need to copy your other files off the hard drive before you do the partitioning as you will loose it. After you have finished with the process you can put them back on there.
I have a Dell Inspiron Laptop Iam planning to make a rescue disk via., Dell Backup and Recovery (DBR) - Basic-Version  Now, it says  w.r.t.  below mentioned link that this process will create two partitions on the external drive.  (Wiping all prior content of course.) DBR_BOOT (25MB used out of 500MB on a FAT32 partition MBR style) DBR_MASTER (9.7GB used out of 921GB on a NTFS partition MBR style); [View:en.community.dell.com/.../19499639] Now, my question is will i be able to save my other-files on the external hard-drive which i will be using for the above mentioned process ???? (as the above process creates two partitions of 921GB & 500MB) Iam planning to save a system-image of my computer on this hard-disk as-well-as i have some 250GB of personal files & videos (Iam going to buy a 500GB hard-disk to do the above-process.....) 
Help regarding preparing a rescue disk on an external hard-drive via., Dell 
Backup and Recovery (DBR) - Basic-Version