Buzzing display / bended palmrest xps 1530

Hi again,

it seams that I do not have any luck with my xps 1530 at all (one month old). I allready post "problem" with Dell Quickset "feature" in Vista.
Namely it is not possible to change network settings (ip, printers, etc...) in Vista as in XP .

Bigger problem was/ is that my XPS came with slightly bended palmrest in the middle, so when you look at laptop from front side you can see that line is curved and small bulge is noticable above touchpad (it's nothing wrong with functionality but thing look just wrong for "new" laptop).

Now NEW problem. My screen (1400x900) start to make "buzzing" noise if is not on full power/full brightnes.
Searching through forum I find out that this is possible inverter problem...
Otherwise I was quite satisfied with quality, brigtness and wieving angle as this screen is LG (not grainy Samsung)
My question is:

1) how I can be sure that new screen will be also LG and not Samsung. Is it possible to demand fm Dell/dealer exactly for same brand display (LG) according to part number ? As I understood searching forum different producer has different part number.
2) As Dell obviously need to change old display Is it possible to "upgrade" LED screen instead of CCFL ?
3) How I can be sure/check later that my replaced parts are new and not refurb ?

p.s.

I ask local dealer in europe (croatia) few days after purchase to check my bended palmrest. They just buying time 7 days as "they are bussy etc..." and check was done cca 10 days after I noticed. After checking from their side they lose another 10 days to answer me what dell can do about it.
When I suggest them to give them back my XPS and just take another NEW one they say it is not possible because this can be done (exchange) only in first 10 days after purchase or something. How to do this as they need more than 20 days just to answer on my first complain !

Any suggestions what to do ?