oooh!!! i just got a new one i've ben wanting to try out [but ever since i got it, i can't remember my dreams]
before i interpret it [cuz i want to try out the book if that's alright] you could check out 500 Dream Interpretations by Helen Bertrand, it's a good one for beginners, it has the more common things in dreams and a couple chapters at the beginning on dreams. you could also check out dreammoods.com, i like that site, and it was one of the first dream sites i was on. [the new book i'm trying out is 12,000 dreams interpreted for the 21 century by Gustavus Hindman Miller]
swimming: augury of success if you're swimming without trouble. dissatisfaction if you keep slipping under the waves.
lake: generally it's the mind. [is the lake clear? or is it polluted? this can alter the interpretation. i'm gonna go with calm clear waters] happiness, good health and fortune are on their way.
Stars: [lots of bright stars i'm guessing] good health and prosperity.
Saturn: discipline and limitations, or rebirth. [it could be either so far]
orange: spiritual growth, personal nourishment, and good times. [this is where things tend to differ, the could could be something you like, so you need to interpret how the colour makes you feel, but overall, orange is a positive colour]
planet: uncomfortable journey and hard work.
drop: good health
overall, this sounds like a very positive, good dream [and this book seems pretty good too, couple things are different from what i'm use to but over all good. thanks for letting me test it out ^_^]