To answer your question on what is comparable between a laptop and a desk top well I would consider them different. The parts may all have the same name but they are much different. The key to a laptop is shoving everything into a really confined space and lower power consumption so the system does not give off much heat. Heat is the killer and it is amazing how hot a laptop can get from running a game. So with that in mind I will give an example the performance of 9600 MGT graphic card in a laptop will be less then a 9600 MGT in a desktop. Everything is tweaked to conserve but give good performance on a laptop. A desktop graphic card on the otherhand will have its own fan which allows them to increase the performance. The processor is the same way the laptop will have lower power consumption then a desk top one because a laptop can not cool the same way a desktop can. The picture below show how compact a laptop is. Notice the copper… that is what channels the heat out and the system relies just on the one fan to cool everything.
I like my HP but it is a media computer with a 9600MGT nothing high end or anything. Only problem I had was a key fell off. They sent me a box the next day to send the laptop back to them... well I had my laptop back in 3 days no questions asked and no money paid at all. That kinda says alot. (1 year full warrenty) It has blueray and hdmi output which if you stream movies which is nice to watch on a big LCD Or even to play guild wars
Look for
1. Dedicated graphics card (well its part of the MB but runs on its own)
Research this site to compare the performance marks (I just picked a card to link no preference to it) make a list of the marks you like then search laptops. look at the cards performance of the laptops you choose then base your decision.
http://www.notebookcheck.net/NVIDIA-...TS.9918.0.html
2. Processor (the faster ones you will pay for it)
3. Ram 4 gig at least... more the better
4. Windows 7 upgrade for free (some companies are offering it)
The rest is flare Screen size definition etc...
Good luck
TBH I still like playing on my desktop just because of the keyboard... I am addicted to my programmable keyboard