When you say minimised page - are you talking about web pages? You do not say which browser you are using, Internet Explorer, Firefox etc. What usually happens is that when you minimise a web page it doesn't show up as a separate item on the task bar.
Most browsers now use tabbed browsing which you can see towards the top of your window - a tab with an x or a +. When you click on a plus you can open another web page which means that you have more than one page open at a time. If you minimise both web pages they do not show up in your task bar. In firefox for example, if you hover your mouse over the icon for your browser in the task bar it should show you a thumbnail of one of the pages you have open you click on that - it maximises and you can then see that page with the opened tabs at the top.
Hope this helps.