Hi Priya (a beautiful name by the way)...
Getting to know the language of the Tarot can be confusing. I hope my thoughts here help you a bit.
First, the Yes/No or option spreads. I've learned that you have to be very specific with the position meanings, and factor in how you will handle reversals. Reversals are a personal thing. For some, an upright card will be read as a "Yes", the "Pro" side of an issue, or and indication to go forward, and the reversal would be "No", the "Con" side of an issue or an indication to hold off and rework your plans. Other readers might consider an upright card to represent the "Surface" issues in a reading, with the reversal representing "Hidden" issues. You have to find a system that works best for you.
If I had a two card Yes/No spread where both cards came up in the same direction, I would read the cards from the perspective of the reasoning behind each answer, not the answer itself. In the end I'd still have to make my own choice using the advice I received.
As for the Celtic Cross, depending on how advanced you are as a reader, it's not the best spread for beginners, even if it is published in nearly every tarot book out there. You have to be able to not only interpret the cards in their various positions, but drawn connections between them. It's hard to develop a story when you don't have a lot of experience. If you have your heart set on doing a Celtic Cross spread, try one of the shorter, modified ones on this site under the Tarot Spreads topic forum. Otherwise Mark K. Greer gives a great description of the full Celtic Cross from a variety of perspectives in her book, Tarot for Yourself, 2nd edition. The ISBN # is 1-56414-588-3 should you have trouble finding it.
Don't let language intimidate you. Speak and read the cards in the way that's most comfortable for you and/or your querent. When I read for another, my "readings" are more like conversations rather than "almighty predictions." I ask questions, admit when I'm stumped by somethings, have my querents free associate on a word or image, and do all sorts of other things that aren't "traditional" but that work well for me. There's nothing worse than someone using big words, or putting on airs just to prove they know their subject. Be confident, of course, but be yourself.
Feel free to get in touch with me any time. I hope this post helped a little!
Blue skies and blessings,
- FireRavem