I'm not too sure I follow your description... Do you mean that the user wants internet pages to open up full screen when he opens Internet Explorer? If so; then you just need to open one screen on its own; maximise it; then shut it down. Windows always remembers the last state you had an internet screen and opens all others the same way. When you close IE; it saves that "state".
If you mean the page is viewed in minature; then it might be a text size issue; if you click on View at the top and select Text size from the list - you can choose something more normal to read...
Let us know if that sorts it.
All the best