Definitely 7200 RPM and ATA66.
The ATA66 and ATA100 standards are just the amount of bandwidth for the <i>IDE controller</i>. ATA100 can do 100 MB/s and ATA 66 can do 66 MB/s.
The hard drives themselves, though are usually only capable of about 30 MB/s max.
So, the speed difference comes in how fast the hard drive spins.
<i>I don't know anything about computers... but I did stay at a Holiday Inn last night...</i> :lol: