My partner opened 1 Club. I held:
S: J732
H: -
D: Axxxx
C: QJxx
She was upset that I bid two clubs rather than 1 Spade. I did not think the Spade suit was good enough to bid. What do you think.
On another "convenient" minor open I had 4 Spades and 4 Hearts, both with two honors, and 8 points. I bid 1 NT, which I thought would indicate that I could support either suit.
I had the same partner both times and caught a lot of flack over these bids. Was my thinking wrong?
Assuming you are playing some simple form of standard american, yes your thinking was wrong on both hands.
Usually the responder is supposed to "bid up the line", giving preference to majors in case she has a 6-9 point hand.
With the first hand, you can either bid 1D or 1S. The reason to bid 1S instead of 1D is that the auction 1C-1D-1H-1S might have a special meaning (4th suit bids can have special meanings) and might show a stronger hand than what you have. Suit quality considerations are very rare when responding at the one level and your hand is not one of those rare hands.
With the second hand, you must bid 1H, and if partner bids 1S you can raise to 2S. 1NT actually denies a 4 card major.
The scoring in bridge gives preference to majors and as a result most bidding systems give preference to the majors. Bypassing 4 card majors when responding is usually considered bad.
Bidding a new suit is usually considered forcing for one round so you should be able to bid your diamonds or spades then return to clubs if needed (i.e. you should be guaranteed to be able to bid up the line as per Aryabhata's answer and still end up in clubs if you want)
You should bid as low as possible to leave bidding room for opener. That suggests that 1 diamond is the best response in the first hand (unless it is artificial but forced and shows a "bust" as some players bid), 1 spade is a close second best, and TWO clubs is the worst, because it "jumps" the bidding when opener may have only a three card suit.
Some partnerships give preference to the majors and say that you should respond one spade with ANY four carder, even 5432. If partner has a four card spade suit, say, KJ76, s/he'll want to play in spades with a 4-4 (eight card) fit. Worst case, it will be 9876, but to have the "worst" four cards on both sides is pretty rare. With a 3-card spade suit and a 3-card club suit, partner may call 1NT to your 1 diamond or 1 spade bid, which your 2 club response precluded.
In the second hand, the lowest reasonable response is 1 heart, four card major. Again, even with 5432. If the opener has four hearts s/he'll raise hearts, with four spades, bid one spade; with 3 spades, 3 hearts, 4 diamonds, 3 clubs, s/he'll bid 1NT. But you're bidding 1NT takes most of these options away from partner.
