OS X and Warranty Question

[cosmokanga2]

I purchased my first Mac in October, a new unibody Macbook Pro and have come across some things I have questions about.

MOD NOTE: If it's in the wrong area please move it.

1. Many people on here I see leave their computers on for days at a time without shutting them down. They only put it to sleep. Within the last two weeks though I have had to shut mine down every 2 days as problems or glitches arise. Today for example SoftwareUupdate would launch but then freeze. After force quitting it 3 times I shut down and restarted and everything was fine.
   
   My first question is: Is this normal or do I have a problem with my system? How would I solve the problems?
   
   
2. Final question regards warranty and repair service. I some how got some very small scratches in an area 5mm x 3mm on the corner of the lid. They are only hair width if that and just on the surface, but would it affect getting service, in particular a swap. We live 2 hours from an Apple Store and I need my mac everyday for school so going without it is out of the question.
   
   Would they not swap it on the spot due to this scratch?

Thanks in advance, this community has helped so much so far!