Windows 7 Starter window size issue and upgrading to home?

I have alot of programs open that extend under the taskbar unless it is set to autohide, I can't figure out how to fix this. It happens with maximized windows and smaller ones. So I have the taskbar set to autohide but prefer not to.

Also, how can I install a better version of Windows 7 which I can actually set my desktop background, still shocked that basic feature was taken away. And if I did would I lose acer tweaks for improved battery life and performance if there is any? Or any that are just inherant to starter since it is for netbooks? What program could I use to backup the original OS so I can reinstall it if I want or is there a recovery on here somewhere? Its a 5032h

And while I'm at it, can the touchpad sensitivity be turned down? I keep touching it lightly with my thumb while typing moving the cursor to the middle of another word. I did just find the off button but it's not in a convenient location.