Before making the decision make sure do u want a PC or laptop because if u have to move from/to diff. destinations for job,study etc lappy would be best...
If u looking for PC then the config. depends on what u want to do primarily with pc....like i need a pc for developing apps/programming in java using netbeans..i would go for pc with 2GB fast RAM n dual core processor....without video cards....
let us know u'r requirements...