As I recall, the calculation of MSA is the height of the highest ground rounded up to the nearest 100ft, plus 100ft to account for man-made obstacles on top of the hill, plus 1000ft (for ground below 3000ft - 2000ft for higher ground). On a planned route, all ground within a certain distance of track should be accounted for, depending on the speed you are flying, and the company/authority rules you are flying under.
As a theoretical question, the MSA in this case would be 3600ft and thus you would not be allowed to go IMC (and thus have to fly at or above MSA) as you would not be in the open FIR. You would have to declare IFR with the controlling authority and fly under their control until you could regain VMC.
If you are flying VFR in the first place, you must remain 500ft clear of the ground, and clear of cloud (again, speed is a factor here). While you remain VFR, your hill is not a factor unless you decide to fly over the top of it. If the weather is such that there is a reasonable risk that you could go IMC while attempting to stay above your 500ft minimum, and thus have to climb to MSA - thus penetrating controlled airspace - you must not fly there unless you have pre-arranged your contingency plan with the controlling authority.*
If your flying experience is such that you have no IF capability, you must not put yourself into a situation where cloud penetration is a possibility, whether or not MSA and controlled airspace are factors. You could very well kill yourself and others - it has happened several times.
Scroggs
*If you ever find yourself inadvertently in this situation, it is an emergency. Get onto 121.5 and call Mayday. Squawk 7700 if you have that capability. If you can't regain VMC, fly at MSA on the most sensible heading you can think of (ie away from higher ground and any lower controlled airspace - this is where pre-flight route study is so important). D&D will auto-triangulate your position and guide you to a safe area to let down, or a diversion airport.