DRIVER_IRQL_NOT_LESS_OR_EQUAL is a dodgy driver error, from what I remember (most likely video card driver, especially if you've got an nVidia card), and yes, I've only seen it happen consistently on Dell laptops, though I don't put it past a Dell PC either

You really need to note the actual STOP code as well though, that number is more useful, then you can look it up on the MS site to see what exactly is wrong. You also might want to look at the Dell site for specific drivers rather than downloading generic nvidia drivers from nvidia, for example.