I use GIMP 2.0 for my manips, but only because Paint is WAY too blocky for me to properly draw things poorly.
I've learned skills and tricks to making things the way I want them without too much hassle. I'm also too lazy to download and learn how to use a new program when I work so well with Paint. Plus, I'm afraid of installing a new program because it might take longer to start up or make my laptop run slow(er). Sometimes, I just want to open a window, paste something into it, test something out on it, and be done without saving or opening a program that takes up a lot of memory. I wouldn't give a crap about memory if not for the fact that my internet window(s) take up most of it, so I need all the memory I can get.
I have no drawing programs on my laptop. If I want to draw something,
I have my ways of getting around the "I only have MS Paint" thing. When I'm done I paste parts into Paint, piecing everything together into a perfect whole.
AM <3 MSP
OTP
For my manips, I always use plain old Paint, mainly because I've been making incredibly shitty art with it for about 15 years, so I knew all its tricks. Now I have the new Paint from Windows 7, which I haven't learned the tricks of, but it has transparency filters and fancy drawing tools.
This. A little different, but basically this.