I've been using "rapidshot" lately, seems to work pretty well, but I'm not sure where I got it, try searching google for it, or you can get YAFSScreen from here at SIMV, you can find it by using the search feature at the top of the page.
Still no linked images allowed around here Paz! Naughty...
One easy way to get a screenshot is to press the "Print Screen" key and go into an image editor (Start->Run->mspaint) and paste it. I use PSP7, and save as JPEG, I've seen some people goto windowed mode just to get a screen shot from some third party screenshot program, BOGUS! just use print screen :-P