[..:: Free Radical ::..]

Why don't you make a macro for saving through mspaint?

btw, mspaint doesn't uses optimal compression settings and does not retain all the details (only 80% quality i.e. optimized for 56.6kbps connection). You can easily see artifacts if you zoom sufficiently and compare with the original snap. Best way would be through photoshop or gimp.
Along with that , there is a freeware tool called StripFile which removes redundant color info and useless metadata from jpegs and gifs.
Use that after you finalize your image. Can reduce size significantly without causing any loss in image quality.