Take out the dipstick and sniff it, if it stinks of petrol then you've a knacked lift pump, if theres half a tank then if you unclip the petrol pipe from the bulkhead and lower it below the engine petrol should wee out, if it doesnt then a blockage is likely, if it does then the pump on is suspect, sometimes petrol can furr up.
The lads here might shout at me but if you have some spray oil, not wd40 but one of the cheaper ones that uses propane as the propellant, then whilst spraying it into the intake the engine should run, this will prove your ignition system, another thing that worked on my mrs's landy after it was stood was to 'pour' about 1/4 spray can lid of petrol down the carb first, not too much or you'll explode the exhaust.