task bar help

I've downloaded the simple vista DX desktop (think thats the right one), and have set is as my desktop but the task bar doesn't show, last night when I was trying to get icons on my desktop I clicked on the internet and the vista DX task bar showed, but know, I have managed to get the icons on the desktop but when I load anything the task bar isn't displayed so I have to keep hitting Alt and Tab everytime I want to go to another programme, any help!!!