I strongly recommend this:
http://www.ruger.com/products/2245Lite/models.html
The Ruger 22/45 is a terrific gun and the "Lite" model is even better.
Don't worry about taking it apart. The first time is a pain, but they're always tight when they're new. Just follow the directions. I've had Ruger .22 pistols for well over 40 years and they always make me happy.
My current one is a MkII that I've tricked out.