From those specs we don't know the speed of the processor. Also, you are playing with an integrated graphics card, and they are never very good.
If you are getting lag and don't mind lowering the resolution, then do it. Bring everything down to low and then see how it runs. If it runs good, then increase settings to what's comfortable.
If you don't mind lowering the resolution, then why didn't yuo just try that on your own, instead of asking about it?
Basically, it comes down to you not having a gaming rig which is gonna make the game suffer.