Sorry to ask, but what is the difference between sRGB and RGB? How do you get sRGB?
I don't think there is just RGB in terms of a color profile, there are several flavors of RGB and basically the difference is what colors are included in the gamut (think of it as what colors are available to paint with). If another program uses a different set of colors to render the image and doesn't have the colors that the photo originally had, it makes a best guess of what it could convert it to and sometimes not what you would hope. If you don't color manage you photos, it's probably best just to keep your entire work flow in sRGB (that's not a certain answer but at the moment that's what I believe). That way when you view in other programs and post to the web you will be pretty safe that they will see what you see. You would use other profiles like Adobe RGB if you want to maximize the available colors since the gamut is bigger and has more available colors to it. This I know isn't a very good description, google or search this forum for color management for more information, there are some good tutorials out there.