You're welcome on the info bit. Now for the hard drive interfaces...
Performance-wise there's not much difference between Parallel ATA and Serial ATA. However, PATA is in progress of being phased out, albeit at a very slow rate. Price differences between the two is beyond me... however, I find that many drives advertised in say Circuit City or Best Buy tend to have PATA drives for cheaper due to rebate inclusions. So you often end up paying a little more just for the SATA interface. While the difference may be in interface and price, the big difference is how your cables are setup, which can affect your overall cooling performance of your system. PATA by most means is a wide ribbon cable that you usually tuck away neatly behind some place to keep your case neat and tidy. But it's wide and sometimes it doesn't tuck away nicely, and thus hurts cooling performance. The definition of that is your airflow within the case may suffer due to PATA's wide ribbon cable sticking out somewhere or anywhere at all. It'd restrict airflow or interrupts it somewhere and can generate higher ambient heat inside your computer.
SATA is developed for two reasons: 1) to improve airflow, and 2) to replace the aging PATA interface with something more beneficial in the long run. I'd explain the difference in technical means but that wouldn't be very practical and useful to you, unless you want me to explain it. SATA uses a smaller and thinner cable which is much more flexible and doesn't get in the way as much as PATA cables do. Its specifications mean it performs better than PATA but only by a small margin. SATA also rid the world of having to set jumpers to identify HDs as master or slave drives. Each drive would be connected with a single SATA cable and you don't have to worry about having to bend your PATA cables in many ways just to move it out of the way.
In the long run, a SATA drive would benefit in a few more ways than one... but to get that, you'll need to spend just a little bit more to get those benefits. However, I think that the extra money spent on getting a SATA drive would then be worth it in the end.
Performance-wise there's not much difference between Parallel ATA and Serial ATA. However, PATA is in progress of being phased out, albeit at a very slow rate. Price differences between the two is beyond me... however, I find that many drives advertised in say Circuit City or Best Buy tend to have PATA drives for cheaper due to rebate inclusions. So you often end up paying a little more just for the SATA interface. While the difference may be in interface and price, the big difference is how your cables are setup, which can affect your overall cooling performance of your system. PATA by most means is a wide ribbon cable that you usually tuck away neatly behind some place to keep your case neat and tidy. But it's wide and sometimes it doesn't tuck away nicely, and thus hurts cooling performance. The definition of that is your airflow within the case may suffer due to PATA's wide ribbon cable sticking out somewhere or anywhere at all. It'd restrict airflow or interrupts it somewhere and can generate higher ambient heat inside your computer.
SATA is developed for two reasons: 1) to improve airflow, and 2) to replace the aging PATA interface with something more beneficial in the long run. I'd explain the difference in technical means but that wouldn't be very practical and useful to you, unless you want me to explain it. SATA uses a smaller and thinner cable which is much more flexible and doesn't get in the way as much as PATA cables do. Its specifications mean it performs better than PATA but only by a small margin. SATA also rid the world of having to set jumpers to identify HDs as master or slave drives. Each drive would be connected with a single SATA cable and you don't have to worry about having to bend your PATA cables in many ways just to move it out of the way.
In the long run, a SATA drive would benefit in a few more ways than one... but to get that, you'll need to spend just a little bit more to get those benefits. However, I think that the extra money spent on getting a SATA drive would then be worth it in the end.