I need a new desktop Tower.?

The tower i own now is pitiful. I mean I'm pretty sure it was once good, roughly 15 years ago. It's a dinosaur and I'm desperate for a new one. It would be my family's desktop so it would have to run World of Warcraft, League of Legends, a few other games (free trials for other MMOs, Warcraft III, stuff like that). My dad likes to take a lot of pictures, so it would have to have enough memory to hold a ton of pictures, as well as picture editing and display software. Don't worry about the graphics card, i have a 9500 GT GeForce graphics card from nVidia that I thought could have things run a little more smoothly on my computer. I'm assuming i could just pop that out and put it in the new tower (correct me if I'm wrong). These requirements along with simple Microsoft Word files, Power Points, anything a freshman in college, a junior in highschool, and an 8th grader will need for homework and school. My tower now has roughly 200GB of memory, 1 1/2 GB of RAM, the 9500 GT GeForce graphics card, and i have no idea what the averages of any of these things are in today's tower models. I really appreciate any help. thanks