Honestly, I have a pretty damn good HP computer for 450, has HDMI adapter, decent battery, and 500 GB HD. The more you pay, the faster the processes the more space it has. Two big things for mac, (well three, one being that they are insanely expensive) if you're really into filming, which I will be majoring in Telecommunications and production (since I already work on the Penn State production crew for athletic events), Macs are simply better, have better software and run faster for those processes, I will be getting one for sure for college as I have been working with them in the offices at PSU. Two, they have a very good base software package, its different than PC, but a lot better with handleing viruses, and overall helps the performance of the computer. All in all Mac=more sophisticated, faster, more towards the media population (more expensive). PC=simpler, cheaper, more towards the gamer as some PC's are super powered with a shit load of shit, thats right, haha I don't know much about those computers though, expect that they are world class but over $5,000.
My .02