Are there any computer geeks in here?

I have an external USB hard drive, 250GB, currently formatted in NTFS. It is "recognized" by my Mac OS X but will not write to it, presumably because of the file system. I thought OS X was straight Unix, which can read and write to NTFS partitions.

Should I format this thing to FAT32? Most USB flash drives are formatted FAT and work just fine on Macs. What is the drive size limit in FAT32? I thought it was 8GB or something. I really don't want 16 separate partitions just to get half of the drive space recognized by my Mac.

What do you use for your dual-configured offices so that one drive can hold both Mac and Windows data on the same drive?

Lastly, any tips for a Mac (OS 10.4) that seems to constantly freeze up and lock? It must think its a Windows PC - I've never seen a Mac freeze up this much.