The other day we were working for the NewYork trade show Artwork and we wanted to take a ManageEngine Opmanager screen snapshot and make a billboard.
Task: What you see on the computer screen is 72 DPI where as on print what we need atleast a minimum of 100 DPI better one of 300 DPI
Using Adobe Photoshop and using your normal screen capture method ALT + Printscreen (to get the highlighted or active window) or just Printscreen (to get the entire desktop), you could get the desired 300DPI
Capture your desired screen
You are done, currently this screenshot is 300 DPI and by using your move tool move the screenshot to your desired artwork