topper,
Dell Notebooks-
The Inspiron line is built for the consumer market with an emphasis on keeping costs low. The Latitude line is built with an emphasis on reliability and business-useful features, even if it costs a little more. Although both should just work fine with onsite warranty at swat.
about the swat dell link, just a word of caution, it might actually be cheaper with special deals on dell's regular site than the swat dell promotion site. It won't hurt to check out both.
Abt PC and MAC, I think you should choose the model you are most familiar with (In your case, PC) so that you won't have to go through all the learnings and troubleshootings again. PCs tend to be quite a bit cheaper (especially if you count in the additional cost of new MAC software while you might already have some PC software). And if you play games (tho might not be realistic in swat

), PC definitely has more support.