If your late father's name is the only name on the deeds, there's a very strong chance that you might have a claim on all or part of the property.
If your late father's name appears on the deeds as a 'joint tenant' (which is the most common arrangement when two people jointly own a property) then, upon his death, his interest in the property automatically passed to the other joint tenant (who was presumably his ex wife). Joint tenants don't own a transferable interest in a property , so it can't be left to anyone in a will (or inherited under the intestacy rules).
If, however, your late father's name appears on the deeds as a 'tenant in common' with his ex-wife, then he owned a transferable share of the property (which would be 50% unless specified otherwise in the deeds) which he could leave in a will (or should have been distributed under the intestacy rules if he left no will).
The most likely situation is probably the second one (where your father was a joint tenant with his ex wife and you can't inherit his interest in the property) but you can't be sure without seeing the deeds. If his ex-wife won't grant you access to them (or you'd rather not ask), then (as long as the property is on the Land Registry) you can access details of the legal ownership of the property, for �3, here:
http://www.landregisteronline.gov.uk
Chris