I think BH wants to do it himself.
Here's another link --
MB Factory Approved Service Products
Unfortunately, this publication and its recommendations are not year-specific for MB vehicles.
Use NO additives in the oil.
Oil maintenance is one of the most hotly debated and opinionated topic on this or any automotive forum. You can search using words like "synthetic oil" and read for hours.
If you want a quick and specific answer, I'll give my opinion.
Considering the age of your car, you should do fine with pretty much any oil with a decent grade that matches your climate and driving habits. Stay away from SA-grade oils (I hear they still exist). Use the higher S- grades, such as SH, or SJ. Store shelves are pretty much filled with only these types. Don't use weird grades like 0W-20 for Florida summer turnpike driving or straight 30W for canadian short trip winter driving.
I think all motor oils are detergent. I'm personally not a fan of high-mileage oils.
I would recommend using regular 5W-30 in the winter and 10W-30 in the summer with 3K oil change intervals. Or you can use a good 5W-40 synthetic oil with 6K to 10K oil change intervals. Mobil is a good name for synthetics, others are good as well.