Del, the pan has to be pretty hot when you start and it has to have a thin little pool of oil in the pan. The heat and the hot oil together pretty much seals up the bottom of the egg immediately. If it's not turning white really fast, it's not hot enough. You can (but don't need to) cook the pepper first which would make it softer and more likely to provide a seal but that is not needed.
Oh--of course your pepper ring (or onion ring) should be cut pretty flat. So use a big knife to get that smooth flat cut.
I pour the egg into the ring slowly if I think the bottom of the pepper isn't properly touching the pan or doesn't have an oil seal to the pan. A slowly poured egg has a better chance of not seeping out if you don't have enough oil.