The Age senile Question of LAPTOP vs TOP?

So, I just bought my first laptop 2 day ago, and compared to a desktop I hate it, zero, it wasn't a crappy lap top, here are the specs:
Blu-ray
NVIDIA GeForce 8400m GT
3 GB of RAM
320 GB Delicate drive
Core 2 Dyad 2.0GHz
Windows Vista
Etc.
It wasn't crappy whatever , but I'm not feeling it, I'm on the verge of returning this $1,300 beast that was on sale all for $800, and active to buy parts for a computer which adds to a total of $902.52. But Completely disowns this laptop in every category except mobility. My Computer specs are:
ATI HD3870 (Better than 8800, but not 8800GTX)
750 GB Hard drive
Core 2 Duo 2.4Ghz
4 GB Ram
Antec 900 Case
Windows Scene Ultimate
530W Muscle Supply
Etc.
Provided you compare for the price, the desktop wins, if you relate the specs, the desktop wins, but is there any secret to why people buy laptops? Besides mobility? Oh yea, the whole reason for the laptop is because October 1st I leave for school, the first of 3 to leave the nest to a diametric state, going to beryllium a freshmen, wish Maine fortune! Also, FIDM (The college) rations students with laptops for the year, but there aren't high-end or anything really so I can get one of those also to use just for school work. But ignore that fact and tell Maine what you would do in my position.