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.
Furnaces, on average, last 15-20 years, heat pumps last 16 years, and air conditioning units last 10-15 years. Tankless water heaters last more than 20 years, while an electric or gas water heater has a life expectancy of about 10 years.