The PS3, if bought from UK will play blu-rays of Region B and DVDs of Region 2. Also note, it will also play region-free DVDs and blu-rays. If your DVD and blu-ray collection is entirely region-free, then you will have no problem playing them with the PS3. Games are usually not a problem. Games are region-coded, but they play with any PS3.
A PS3 bought in India will have Blu-Ray Region Code C and DVD Region Code 5.
Now, when it comes to discs, blu-rays bought in India "generally" are not region-coded, they are region-free. DVDs may or may not be region-coded. It is best to check the packaging before buying discs to see if they are region-coded or not. If you will be importing discs from UK or US, note that US/Canada strictly implement region-coding, i.e. they are coded Region A for blu-rays and Region 1 for DVDs, hence they can only be played back on PS3s bought in the US. UK discs, again you'll have to ensure that the region code matches that of your PS3, depending on where you buy it from.