Two years is not a long time to be sitting idle. The electrolytic caps should be okay (assuming they were okay going into storage).
You should not have a problem with speakers not attached if you don't put a signal into the amp.
Elizabeth's approach would be a not to difficult to implement safety measure. Be sure to have a reasonably long time between turning on the amp again. Some tubes hate being turned on again immediately after being turned off. If I do that with my power amps, I sometimes get a tiny flash from the rectifier.
You should not have a problem with speakers not attached if you don't put a signal into the amp.
Elizabeth's approach would be a not to difficult to implement safety measure. Be sure to have a reasonably long time between turning on the amp again. Some tubes hate being turned on again immediately after being turned off. If I do that with my power amps, I sometimes get a tiny flash from the rectifier.