1. Any size - Small or large; it does not matter.
2.10 - 12" - Good size for a lot of travelling.
13 - 14" - Good to carry around from one class to another.
15 - 16" - Standard size to balance between portability and performance.
17+ - Good size for entertainment like watching shows and movies.
Surf the internet - Browsing youtube, checking email, watching netflix, visiting websites, etc.
Type papers - Typing papers and documents on word, spreadsheets or other office applications.
Type a lot of numbers - Typing numbers often for data entry, calculations, etc.
Save a lot of files - Saving a lot of pictures, music, videos and large documents.
Video chat - Using skype, video conferencing.
Editing
Casual media editing - Editing photos and videos once in awhile, nothing serious.
Professional media editing - Editing a lot of photos and videos everyday, it's my job.
Entertainment
Share laptop screen with a TV - Connecting the laptop to a TV to share the screen.
Watch DVD movies - Watch DVD movies and save files into CDs.
Watch Blu-ray discs - Watch blu-ray movies on your laptop.
Gaming
Play light games - Play games like Minecraft and Sims.
Play heavy games - Play games like Crysis 3 and Battlefield 3.
Do I want any special features?
Touch screen - Control the laptop by touching the screen without using the touch pad or mouse
Tablet hybrid - Turn your laptop into a tablet
Backlit keyboard - Keyboard l