It IS the roast that is the difference. The only real difference in the beans is that some beans taste better at a higher roast than others, so they are more appropriate for espresso. Your Italian grocery coffee company may be using the espresso label for marketing purposes, but in general, espresso coffee beans can be the same beans that are used for "regular" coffee, but roasted to a French or Italian roast level, which is darker than City or Full City.
Since the advent of Starbucks, many roasts are much darker than they used to be. Dunkin' Donuts coffee, which is a Full City roast, used to be the norm, but now a French seems to be what you can buy.
I roast my own coffee and take it to just into the second crack which is, generally, a Full City roast...a point where the character of the coffee predominates rather than the flavor of the roast. There is more information about roasts at Sweet Marias where I buy my green beans, and reading through the site will give you way more of a coffee education than you probably ever wanted.
So, yes, you can use the coffee you have to make brewed coffee. It will probably be roastier than you would normally have, unless it is just a marketing ploy, in which case it will taste normal. Consider how long you have had this coffee; if it has been shelved for a while "normal" probably won't be all that great, since freshly roasted coffee is, generally, way better than old coffee. But as long as the oils aren't rancid, it is more likely just going to be bland.
Posted as answer by request of @BaffledCook:
Here's an slightly informal blog post outlining changes in taste between varying degrees of freshness in the grind of a coffee.
http://investigationsblog.wordpress.com/2010/03/03/do-i-really-have-to-grind-coffee-right-before-brewing-it/
The short version is that the coffee starts losing freshness as soon as it is ROASTED. The longer it sits the faster it goes stale. The more surface area it has (ie: you've ground it up; also, the finer the grind), the faster it goes stale. The more you expose it to air, the faster it goes stale. So, seal your coffee in an air tight container at room temperature. And grind as close to the time you add water to it as possible.
How much of a difference detected depends on the the actual coffee been, the roast, the taster's taste buds. If you buy a bean that's been sitting on the shelf for 3 months already, you will probably notice less of a difference than a bean that was roasted last week. I buy beans that are roasted and sold within a week, and I DO notice a difference if I leave the grounds for a day or two before drinking.
Best Answer
If it's refrigerated, it'll last for at least a week, as long as you didn't pre-dairy it.
Unrefrigerated, I wouldn't trust it for more than a day. Coffee is a crappy growth medium and it should start out the next best thing to sterile, but, even covered, its going to start to get moldy.
Obviously if you add dairy, then you're dealing with that dairy shelf-life, and that isn't very long at all.