Life can't be easy these days for Disney (DIS) - Get Report CEO Michael Eisner.

A few months ago, all he had to worry about were the difficulties of running one of the world's largest media and entertainment conglomerates.

Now, suddenly beset by grumpy shareholders and acquisitive cable operators, Eisner must contend with a threat much closer to home. Even as he struggles through operational problems seemingly immune to a quick fix -- poor ratings at the company's television network, for example, and a theme park business that's hurt by economic problems and geopolitical jitters -- he finds a snowballing perception that he's not up to the task.

Disney rejects the criticism, pointing to his central role in the company's improving performance. But the knives are out all the same.

"You don't have the same fire in the belly because you're a well-fed billionaire," says one media investor and longtime Disney observer, speaking on condition of anonymity.

Eisner's foes are many. Roy Disney and Stanley Gold, who resigned from Disney's board last year, have grown increasingly vocal in their criticisms of the company, embarking on a campaign to have shareholders withhold votes for Eisner and three other board members at the company's annual meeting on March 3.

Meanwhile,

Pixar

(PIXR)

, the computer animation studio behind such Disney hits as

Toy Story

and

Finding Nemo

, publicly broke with Disney last month. Pixar CEO Steve Jobs made it abundantly clear he thought Disney's storied animation studio was a mere shadow of its legendary heritage.

And just when Eisner thought it was safe to hold a two-day meeting for analysts at which he could discuss stronger-than-expected first-quarter results, here comes

Comcast

(CMCSA) - Get Report

swooping in with an unwelcome bid for the company.

After that Wednesday, it began to seem like everyone was just piling on. Within three hours of Comcast's announcement, a Disney shareholder filed a class-action suit in Delaware Chancery Court, alleging that Eisner and the board had breached their fiduciary duties by Eisner's rejection, earlier this week, of a private overture from Comcast. (Later on Wednesday, Eisner said the board had met in response to Comcast's publicized offer, and had instructed management and its advisers to prepare an in-depth analysis of the proposal.)

Also on Wednesday, criticism of Eisner came from a new source, as the proxy advisory firm Institutional Shareholder Services recommended its clients not support Eisner's re-election to Disney's board. Disney called the recommendation "inexplicable and unjustified," saying Eisner "led the very changes that resulted in a board dominated by independent directors" and reiterating Eisner's "commitment to governance and transparency."

Though the board has been supportive of Eisner, particularly in defending Eisner against the disgruntled former board members' accusations of mismanagement, Comcast certainly timed its unsolicited merger bid when Eisner looked his weakest.

"It's a clever time to attack the guy, given all the background noise" of Roy Disney's anti-Eisner campaign, says the media investor, who doesn't hold shares in either Comcast or Disney.

Comcast CEO Brian Roberts -- arguably a well-fed billionaire himself -- was coy about why he went public with the offer Wednesday, after a private approach to Eisner was apparently rebuffed earlier this week. But Roberts' comments at a press conference suggest his timing wasn't completely random.

While speaking politely at the news conference publicizing their bid, Roberts and Comcast Cable President Steve Burke, a former Disney executive, subtly used rhetoric similar to that already employed by the dissident directors and Pixar's Jobs: that Disney's glory, under Eisner, has faded.

At various times in the course of their news conference, Roberts and Burke mentioned the attempt to "restore" the Disney brand, "restoring" the company's operating performance, a chance to "reignite" the business, the need for Disney's animation to "regain" its prominence, and the possible "revitalization" of the theme parks.

The deal, as they framed it, is not about improving Disney, but about rescuing it.

Whether Comcast executives are better suited for that task than Eisner is up for debate.

The anonymous investor tends to side with Comcast. What has happened to Disney, he says, is that the company's heritage and past success have made management complacent -- the same thing, he says, that set the stage for

Sears

(S) - Get Report

to be overtaken by

Wal-Mart

(WMT) - Get Report

.

On the other side of the debate, Vogel Capital Management head Hal Vogel suggests that Disney has done all right considering the difficulties it has faced in recent years. "I think they've done reasonably well in a tough environment post-9/11," he says. "They've weathered the storm reasonably well."

Vogel also says that improving Disney's results would be harder than Comcast indicates. "They've done a lot of cost-cutting already. ... I don't think Comcast is going to have an easy job in improving performance quickly," he says. "You don't just snap your fingers and create hit programs on ABC, for example."