I will try to give you some "g-e-n-e-r-a-l" info.
This is a very personal thing and everyone has there own
ideas and needs. You are getting the opinion of one person.
Everyone else will have diferent opinions, but in the end, you have
to decide and do something.
First of all, you bought a 200 gb drive so you must have some idea
what you are going to put on it. Give this some thought.
Second of all, Windows OS files are a couple of gigabytes long.
Third of all, you don't want too many partitions, cause you will go nuts
trying to keep track of them
So for you, I would suggest that you use 2 or 3 partitions, mind you, I don't know what your
needs are and don't how you are going to organize your files.
So what the hell, go with C:=50 and D:=150
or....C=50 and D:=50 and E:=100
or say that I am all wet and use what you want cause I don't know what it is.
Just do it, and you will find out how it works out, thats what we all d.
Then next time we do it diferent..
Just remember, there is no perfect solution
Good Luck, I am leaving.