The debt crisis in Europe could go either way. Friday’s big meeting could cheer up markets big-time, or it could cause investors to head screaming for the hills.

Either way, there’s a lot of uncertainty and fear out there at this moment. If you believe in the old Warren Buffett adage to “be fearful when other investors are greedy and greedy when they are fearful,” now is the time to be greedy. Responsibly greedy, of course.

So where should you invest if you’re thinking of plumbing the depths in Europe? Here are a number of options to consider for those who might be optimistic about the euro zone or thinking long-term about a recovery in the region:

European ETFs by Nation

As should be no surprise, there’s no shortage of ETFs that cover individual European nations. But be advised — based on the headlines about who is better off in regards to their debt, some of the outperformers in 2011 might surprise you. Consider that the iShares MSCI Spain Index Fund (NYSE:EWP) is down only about 8% year-to-date while the iShares MSCI Netherlands Fund (NYSE:EWN) is off almost 16% YTD despite the country holding an AAA rating from S&P. At least for now. Clearly there are more things at work in a nation’s economy than its sovereign debt, so examine each country-based ETF carefully if you go this route.

Broad-Based Europe Funds

A simple way to play Europe if you believe in brighter days ahead is a diversified investment like a mutual fund or ETF. The index-based Vanguard MSCI Europe ETF (NYSE:VGK) is a great option with its rock-bottom 0.14% expense ratio. Remember, most active managers don’t beat their benchmark — so this low-cost way to buy Europe is the most cost-effective for longer-term investors.

Other funds are out there with slightly different flavors, such as the iShares MSCI EMU Index Fund (NYSE:EZU) that focuses on the European Monetary Union nations in the euro zone (that’s the “EMU” in this name) but charge higher expenses even if they are pegged to indexes just like VGK. If you want to trust an “expert” to pick stocks for you, a decent actively managed mutual fund is the T. Rowe Price European Stock Fund (MUTF:PRESX). Dean Tenerelli has been at the helm since 2005, and expenses of a little over 1% are reasonable for this fund that garners a four-star rating from Morningstar.

Leveraged Europe Funds

Not for the faint of heart, aggressive investors can see twice the profits — or twice the losses — with the leveraged ProShares Ultra MSCI Europe ETF (NYSE:UPV) that will try to double the performance of Europe stocks. It’s worth noting for the bears out there there’s also the ProShares UltraShort MSCI Europe Index Fund (NYSE:EPV) that goes up twice as fast as Europe goes down. Use stop-losses and tread lightly if you go this route.

ADRs of European Companies

American depositary receipts, or ADRs, are the best way to access international investing. These essentially are stand-in shares for a stock that trades on a foreign exchange — but you get the ease and liquidity of trading on the NYSE or Nasdaq. What’s more, the top tier of ADRs must adhere to U.S. GAAP standards — filing a 20-F annually and following 6K rules for any shareholder disclosures just like the bluest of the domestic blue chips. Some of the top ADRs you might want to consider are:

• French energy giant Total (NYSE:TOT). This oil and gas company pays a nearly 4% dividend (semiannually, however) and could benefit from a broad global recovery and increasing crude oil demand in the years ahead, as well as a euro zone rebound. There are a lot of ways to play oil and get a dividend, but Total’s $115 billion market cap gives you some stability if you’re leery of other European options right now.
• Spain’s Telefonica (NYSE:TEF) is a telecom powerhouse that also offers a plump dividend twice a year. Based on previous payout rates of around 85 cents, that gives investors a great annualized yield of around 9%! Like domestic telecoms, Telefonica might not have breakneck growth ahead — but income like that and the prospect of a value buy amid euro zone negativity could work in your favor with a great dividend stock like TEF.
• Switzerland’s Novartis (NYSE:NOV) is a health care powerhouse that has seen 10 consecutive quarters of year-over-year revenue increases. It pays an annual dividend of around 3.7% based on historical data, and its focus on generics, vaccines and emerging markets could pay off down the road.

European Pink Sheets

While euro zone stocks that trade as ADRs have a significantly higher daily volume and stricter SEC oversight than those that trade on the pink sheets, don’t count out these thinly traded OTC stocks.

Take food products giant Nestle (PINK:NSRGY), one of the biggest consumer brands in the world that trades as a pink sheet. Nestle pays dividends once a year, typically in April, and the payout has been sweetened 15 years in a row to a current yield of more than 3%. Even over the counter, Nestle trades more than 500,000 shares daily — so it’s more liquid than some “legitimate” stocks on domestic exchanges.

Other Europe stocks aren’t as liquid. Dairy giant Danone (PINK:DANOY) only trades about 100,000 shares. But they also can provide opportunity if you do your homework.

Jeff Reeves is the editor of InvestorPlace.com. Write him at editor@investorplace.com, follow him on Twitter via @JeffReevesIP and become a fan of InvestorPlace on Facebook. As of this writing, he did not own a position in any of the aforementioned stocks.