I would have thought an effective medium for backup would be a USB Flash Drive (not the DVDs I am intending to use), assuming you are not going for a second internal or external Hard Drive, You need to get one big enough in GBs to adequately store what you intend to backup. In the UK there are plenty available, their price seems to have come down quite a lot and I am again assuming this also applies to India?
With a big enough USB Flash Drive there will be no repeatedly inserting fresh DVDs as the backup proceeds, you will have everything on one storage device, very easy to carry around (including no need for a Writer / Reader) as you just plug in to your PCs USB port(s), reliable, according to most users (I personally have found them less so for some reason), reasonably fast (more so than DVDs), quite robust. I am almost persuading myself to buy a big capacity USB Drive for carrying out my backup! .
A useful tip I have had from AOMEI is that with Backupper's mid level compression setting, your backup should take about half the space of the original files,but they recommend allowing for two-thirds to be sure.
I am no expert, I am only just planning my second backup and the first, with a different program, had some problems. Other Forum members with much more expertise may comment and take a different view.