Hi Sue,
I brought Sterling and it was possible to change money at all hotels, except Tiger Moon (Ranthambore). Around half the group got the notorious Delhi Belly, but we were all able to carry on regardless and no one came a cropper thankfully! Tipping is expected everywhere, so when you first change money as for some small denomination notes. Ring your credit card company and tell them when you will be away (I do this for all foreign holidays), otherwise you may have problems using it, as they may put a block on transactions if they think it is being used fraudulantly.
Have an amazing holiday!
Best wishes,
Bob