Macs and Linux wont but any Windows box that reads NTFS will.
You probably shouldn't be formatting externals with NTFS anyway. FAT32 is perfectly adequate, and can be accessed from any system, including Mac, Linux, and pre-NT Windows machines. There are also fewer issues with the drive being unrecognized by newer windows installations.
eSATA or IEEE1394b are faster than USB, but are less common on older machines. If your PC supports them (and you don't need to use it on other machines), go with eSATA, or if you can't, IEEE1394b ('firewire' for you Mac people)