Best laptop in 40,000 Range

Budget : 40,000
Size: 15inches
Primary functions: To read PDF books , (nearly 60GB size) , To view XRay--CT--MRI pics
Likes: Dell/HP
Screen resolution: 1080p(hoping this will help in visualising XRay pictures clearly)
Configuration: RAM:4GB
Memory:1TB
(Also let me know if 4GB RAM is enough to handle 1TB memory . If it drags the performance I will settle with 500GB though)
Confused between i3 and i5.
Kindly suggest.
Thanks in advance