One of the best quarters in stock market history came to a close today on a positive note, as the market ended mostly higher. After having closed 2011 with worries about everything from a European collapse to budget woes in the U.S. and a slowdown in China, investors now seem to see the glass as being half full. The Dow Jones Industrial Index (INDEX: ^DJI) closed today up 66 points to 13,212, falling just shy of gaining 1,000 points for the quarter.

Let's take a look at some of the best-performing Dow stocks today.

Disney (NYSE: DIS), up 1.8%
The company that brought you Mickey Mouse benefited from an analyst upgrade at Lazard today. But the more interesting news from the company came from a collaboration between Disney and a Japanese gaming platform.

Disney said it would develop social games for mobile platforms with DeNA based on Marvel characters including Captain America and Iron Man. The move could provide some free publicity in Japan for the films based on the same characters. More importantly, this small collaboration could mark just the beginning of Disney's move to get more serious about using its content on mobile and social platforms.

Hewlett-Packard (NYSE: HPQ), up 1.4%
Hewlett-Packard has gone through a number of big strategic changes and acquisitions over the years. But as it tries to rebound from a long slump, HP should probably tread carefully before trying to buy its way into another big merger.

Some have speculated that HP could try to boost its mobile presence by buying out Research In Motion (Nasdaq: RIMM), as it reportedly considers exploring strategic options. But such a move would probably only compound the challenge that CEO Meg Whitman faces in trying to develop a coherent strategy for HP going forward. HP is better off consolidating its strengths and moving forward to try to refocus itself on its core business.

Merck (NYSE: MRK), up 1%
The pharmaceutical industry used to be all about developing new drugs. Now, drug companies are starting to turn to their biotech peers for guidance -- and growth.

With Merck's initiative earlier this month to establish the California Institute for Biomedical Research, the drug giant is trying to find ways to leverage R&D spending in directions that are most likely to bring new ideas. Whether the moves bear fruit will take years to figure out, but for now, Merck is holding its own by keeping up with its competitors on this new investment front.

Marching on
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