It's time to go shopping for shares again, but where to start? Struggling insurer Aviva (LSE: AV.L)? Cut-price Tesco (LSE: TSCO.L)? Or recovering oil major BP (LSE: BP.L)?

There are plenty of great stocks to choose from, and I'm enjoying doing some window shopping. So here's the question I'm asking right now. Should I buy BHP Billiton (LSE: BLT.L) (NYSE: BBL)?

Of mice and men (and miners)
Miners are for men. If you're feeling all pumped up by prospects for the global economy, you'll want to grab a fistful of mining companies such as BHP Billiton, Rio Tinto (LSE: RIO.L) and Vedanta Resources (LSE: VED.L), and prepare to hit pay dirt.

But if you think the economy will squeak instead of roar, you may scurry for cover instead. The question I'm asking myself is: Am I a mining man or a defensive mouse?

Going down
The miners weren't looking too macho in the first half of this year, with some falling up to 30%. BHP Billiton was down 16%. Suddenly, mining stocks were looking cheap.

Then European Central Bank president Mario Draghi upped his efforts to save the euro and the U.S. Federal Reserve announced QE3, and commodity stocks rebounded, as they do whenever central bankers ease monetary policy. All that extra liquidity has to go somewhere.

BHP Billiton is back at £19.11, at time of writing, although well off its 52-week high of £22.

Olympic loser
Aside from virtual money printing, is there a case for investing in the miners? We're supposed to be in the middle of a commodity super-cycle, but the industry is clearly beginning to have its doubts.

BHP Billiton saw its profits fall 35% in the year to August, largely thanks to weaker commodity prices. After postponing its plans to build the world's largest open pit mine, the $30 billion Olympic Dam project in Australia, chief executive Marius Kloppers predicted a continuing long-term decline in prices. That's always a particular problem for miners, because of their high fixed costs. BHP Billiton is retrenching, with no major projects planned for 2013.

China syndrome
Blame it on China, partly, whose manufacturing industry has now fallen for two successive months. The country's GDP growth has now slowed to "only" 7.6% a year, a three-year low. The forthcoming change in Chinese leadership will only add political uncertainty to economic uncertainty.

Then again, if China's new leadership offsets the slowdown by going on a spending splurge, then mining stocks may extend their recent recovery.

Recovery stock?
BHP Billiton is nicely diversified, with the group's operations divided into nine divisions, covering areas such as base metals, petrol, iron ore, coal, diamonds, and gold. It employs 41,000 people across 25 countries, but despite its size, it remains at the mercy of events it can't control, including global demand, currency movements and natural disasters. Investors must brace themselves for volatility.

BHP Billiton's prospects could brighten if it is correct in predicting that the global economy will stabilize in the first half of 2013 then start to pick up. It is also a net beneficiary of the rising oil price.

Yielding 3.6%, covered 2.9 times, you get a reasonable reward for buying and holding this stock. On a forecast price-to-earnings ratio of 11 times earnings for June 2013, you aren't paying over the odds, either. Nothing wrong with BHP Billiton; the question is, is there anything seriously wrong with China?

I'm holding, but I'm not buying right now. Or maybe I just need to man up?

One stock on Buffett's menu
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Harvey Jones owns shares in Aviva, BHP Billiton, and BP. He doesn't own shares in any other company mentioned in this article. The Motley Fool owns shares in Tesco. The Motley Fool has a disclosure policy. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days.