If the weather is bad, and you'll have to spend time indoors, then check out the '''Deutsches Museum''' (German Museum). It's past the "Isartor" at the eastern end of the downtown area, and a huge museum that can take more than a day to get thru. It's probably best if you take on of the trains that runs under the downtown area (either from Karlsplatz or Marienplatz) in the direction of "Ostbahnhof.
=== Excursions around Munich ===
Munich is pretty central to a few places you'll wanna see, but although it's possible to reach some of those by public transportation, some of them involve multiple transfers etc. I would recommend, that you for at least 1 or 2 days, while in Munich, get a rental car, and drive to those places. it makes things alot easier. A good rental car company, which typically can accommodate you on the spot is "Sixt". You can also ask the Hotel for help, they probably even bring you the car.
==== Neuschwanstein Castle ====
One of the destinations that are somewhat hard to reach by public transportation is the Neuschwanstein castle, but it's only about 90 minutes by car. It's the castle that inspired Walt Disney for his Disney Castle. The place can get quite busy by 10 or 11 AM, so if you get going early, you have a chance of missing long lines and a large crowd. Just do the tour, walk up to the bridge with its magnificent view and "get out" before the crowd hits the place.
==== Linderhof Palace ====
About an hour drive away from Neuschwanstein is '''Schloss Linderhof''', the only palace that the Bavarian King Ludwig II was able to finish. It's typically not as crowded as the Neuschwanstein castle, and the 1 hour drive via Reutte has some of the best views the Bavarian Alps have to offer (you cross into Austria, so don't forget your passports). You'll also come by the drive up to the "Zugspitze", Germany's biggest mountain. If you plan a 2-day trip for this, I recommend a overnight stay in '''Garmisch-Partenkirchen''' (make sure to have reservations). This place held the first Winter-Olympics ever, and has some magnificent views around the Alps. From there, you'll return to Munich via '''Oberammergau''', another alpine village worth to get out and take a stroll around.