If they will allow you to, take a Live Linux CD with you to the store, and see if they will let you put it in the CD-ROM/DVD-ROM drive and load it. From there, you can see more what the laptop can do.
My first DOS laptop came with 512K RAM and 2 3.5" Floppy disk drives. CD Drives didn't exist back then. A 10MB HDD would have cost several hundred dollars. Monochrome display. 24 pounds of portable weight with the battery, which lasted about an hour. It was just too heavy to take to college classes at the time. DOS doesn't have as much system requirements, so they can make the hardware cheaper as well, which I suppose is another reason for making them that way.