Would've been better with Harrison Ford

Although it is amusing watching Arnie try to pull off The Everyman role. Which is probably what Verhoeven intended.

While he isn't the best actor, Arnie adds a certain charm to the film. For instance, I can't imagine another actor saying the cheesy one liners the way Arnie does. A line like "Get your ass to Mars!" becomes forgettable with any other actor. Not to mention he has the sort of build that lends believability to action scenes, even if it might be hard to believe someone like that works in construction to begin with.

Imagining Ford in this role just doesn't feel right.

Nah, I think it works with Swarzenegger because he does look like a secret agent and therefore it makes more sense to him that he's not a regular Joe.

I like Arnie in this, although I think Ford would have done a fine job as well.

Arnie's pure massiveness allowed the action scenes to feature more bad guys to gang up on Quaid. Besides, who else could deliver this line quite like Arnie?: "Come on Cohaagen, you got what you want! Give these people air!"

It's a great movie, probably would be good with any actor in the leading role.

this was from trivia
Producer De Laurentiis' initial vision of the film's hero Douglas Quaid (originally named "Quail")/Carl Hauser was decidedly more in line with Dick's short story: A schlubby office drone who dreams of a more exciting life. With this characterization in mind, his first choice for the part was Richard Dreyfuss. Over time, the desired machismo of the film's leading man increased, prompting suggestions like William Hurt (courtesy of David Cronenberg who was originally set to direct) and Patrick Swayze. Despite the gradual growth of Quaid's imagined virility, there was a limit to how far De Laurentiis was willing to stray from the original character. He insisted that someone like Arnold Schwarzenegger was out of the question for the part and even turned down the Terminator star when Schwarzenegger first expressed interest in the role. Arnold really wanted the role though. He saw an opportunity when De Laurentiis' production company, De Laurentiis Entertainment Group, went bankrupt. The actor convinced Carolco Pictures, with whom he had recently worked on Red Heat, to purchase the rights to Total Recall. The coveted role of Quaid was not the only thing Schwarzenegger won in the transaction: In addition to being welcome to recruit the director of his choice (as a big fan of RoboCop, he picked Paul Verhoeven), Schwarzenegger maintained authority over all creative aspects of the film, script, production, and even elements of distribution.

also:
Christopher Reeve was offered, but turned down, the role of Douglas Quaid.

Jeff Bridges, Matthew Broderick, Richard Dreyfuss, Mark Harmon, and Tom Selleck were each considered for the role of Quaid.

Nicole Kidman and Alexandra Paul were considered for the role of Melina.

Ian Holm was considered for the role of Vilos Cohaagen.

Totally, Arnie is a lousy actor. But, on another hand, the story didn't necessarily called for a "good actor" but rather a though and muscular guy. Hence, Arnie fitted in just perfectly.

The whole movie wouldn't have happened if it wasn't for Arnie, he basically saved it from development hell or being shelved.