Every laptop on the planet should wake up as soon as u open the lid. I wouldn't buy any if it doesn't do that.
Some don't.
@OP: Go to Device Manager, expand the "System Devices" section, and look for your laptop's lid (I want to say it's listed near the top, something like "Lid ACPI.") Right-click on it and select "Properties." If you have a Power management tab in the Properties Window, you should be able to wake the laptop with the lid. If not, the feature may not available.