R Dell Laptops from Target/Sam's OK? Grandkids need one.

Hi,
The grandkids need at least two computers for schoolwork. I've read that you can get Dells off the shelf at Target/Walmart/Sam's/Best Buy, etc.? My question is this: do these off the shelf models have enough of what young people using computers for school need? Can they access the internet, wifi, etc., and do they come loaded with basic word processing and powerpoint programs for schoolwork?

Also, what's a reasonable price to pay for these? Does Dell support technical issues?

Thanks for any feedback anyone can provide.