First off you should be able to format your current external into HFS+ (Mac OS Extended) with Disk Utility.
Anyways the Lacie's are generally
overpriced and you do not know what brand of hard drives you are really getting. Really, the best method for both price and performance is to purchase an external enclosure and install a hard drive into the enclosure. This is quite easy to do.
As for the hard drive to purchase I would recommend a larger drive, 500GB minimum. You would not believe how quickly video will eat up disk space. My recommendations for the different components to purchase are at the end of this post.
My recommendations for an interface would be for e-sata for two main reasons.
1. External Firewire 800 enclosures are very expensive. On newegg.com the cheapest enclosure runs $70 while you can purchase an express card for esata for $35 and a well rated enclosure for another $35 to $40. This price difference would be far more noticeable if a second external is purchased.
2. While no current hard drive will max out either standard. As I recall, one controller is used to run both firewire 400 and 800 on the Macbook Pro. So if a firewire 400 device is attached, such as a camcorder the speed defaults at 400mbps which some current hard drives can max out. While a separate esata hard drive will not take any hits in performance.
For selecting a hard drive a recently responded to another post that is applicable for you too.
I find tomshardware guide to be extremely useful.
Since you are looking at large hard drives the Western Digital 750GB Caviar SE 16 WD7500AAKS just got a very favorable review.
http://www.tomshardware.com/2007/07/06/record-making_hard_disk/
For general reviews:
http://www.tomshardware.com/storage/index.html
For the Hard Disk Charts:
http://www23.tomshardware.com/storage.html
These charts are extremely useful when choosing a hard drive. It consists of quite a thorough list of hard drives. You can compare two hard drives against each other and see how they compare against other hard drives, as well. When using this list make sure to check the ENTIRE model number.
There are also updates to lines that do not show up in the Hard Disk Guide, hence the importance of checking entire model numbers. I was looking at the Hitachi T7k500 HDT725032VLA380 320GB SATA II hard drive that got really high marks the the hard disk charts compared to other hard drives. Then I ended up getting the T7K500 HDT725032VLA360 it was nearly identical in the technologies incorporated in the previous model rated on TomsHardware; Native Command Queing, Perpindicular Recording, Low Surface Temps. The only difference between the two is that the new one I got had a higher disk cache 16MB versus 8MB.
For the adapter card this one from Rosewill gets good reviews, it is cheap, has two ports, and is Mac compatible.
http://www.newegg.com/Product/Product.aspx?Item=N82E16839200006
For a hard drive I like Hitachi they are what I currently use. Since they are fast, relatively quite, and relatively cool when compared to other drives I have owned and going by reviews I have found
For 500GB:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822145137
If you want 320GB Seagate is good:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822148140
As for the enclosure these are pretty ugly looking but have good customer reviews and are cheap.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817145167
http://www.newegg.com/Product/Product.aspx?Item=N82E16817173043
If you want a pretty one it will cost you.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817198011
Some other things to think about. How important are your videos, you may want a second hard drive for backing up files as DVD backup is quite time consuming and a failed hard drive is a major pain, make backups. What format to use with the hard drive, for most uses HFS+ (Mac OS Extended) will work fine, Mac OS extended (Journaled) is not really necessary. Though Journaled is the default selection it is really for RAID arrays and Servers, the Journaled System does impact system performance and generally is not very useful for single drives on a standalone desktop or laptop.