I've half a mind not to help you, because you didn't even bother to check that you'd asked this question in the appropriate section.
You're asking how long a piece of string is. The latest alienware laptops would run Mass Effect without a problem, but then a cheapo laptop from PC world probably won't.
You need a laptop with a decent graphics card/chip. I'm more familiar with desktop graphics, but I know that the xbox 360 gpu is 3 or 4 years old now. It's equivalent to an ATI 1900 xtx, so if you can get a higher specced GPU than that, you should be ok. Check out my Tom's hardware link for a GPU comparison chart. It's a bit old, but it should give you the info you need.
How can you be considering buying this game and not know what it is about? Strange person. It's an RPG set in space and was originally intended for the xbox 360, so it's very console oriented. I think it's made by the same people who made the Knights of the Old Republic star wars games.