Hi there Sandra,
Comparing Disneyland to Walt Disney World is like comparing apples to oranges. In many ways, they are both the same, but they are also very, very different. The first thing you're gonna notice is the size. Disney World will seem huge compared to Disneyland and everything will be more spread out. I visit both resorts frequently throughout the year, and it's like to completely unique experiences.
Although the parks do overlap on certain attractions, I encourage you to not let that deter you from experiencing one you've already tried at Disneyland. This is because, the attractions are different at both resorts and it can be a lot of fun to try to pick out those unique features.
Since your only going to have 2 days in the parks, I suggest you choose the 2 parks you'd most like to visit, and go full throttle. I am not sure of the ages of your children, but I'd probably recommend Magic Kingdom and Epcot.
I answered a similar question regarding the
differences Disneyland and Disney World and I thin you'll find it helpful.
Best Wishes,
Amanda F.