Surgery - Colorectal. In brief: Yes, most docs can. Most hemorrhoids should first be treated by conservative measures, such as bulking the stools, education to avoid bad habits like straining, sitting for long periods of time, etc.
Either system will have a burner. 23 years may very well be beyond the typical life expectancy of a oil burner, but a furnace or boiler should last considerably longer than 23 years. The boiler of my house here in MA is 58 years old and still works fine. I am starting to consider replacements, however.
Fact: Heating oil systems have a longer life. The average life expectancy of an oil heat appliance is 30 or more years if they are properly maintained. The average life expectancy of a natural gas furnace is only 11-14 years. And, the efficiency ratings of new heating oil systems range from 83% to 95%.