You can not do anything about HDD rotation noise. Period. Just think about it - it is 7200 RPM! For comparison, put a 7000 RPM CPU HSF (like Thermaltake 6cu+) - just hear that noise (I had a chance to hear several HSFs at that speed - they sound like Apache gunship!). You can (maybe can, maybe can't) only set maxtor's access times using AMSET program. Any CPU HSF rotating more that 5000 RPM is considered as loud.
My HDD is Maxtor 80 GB D740X with ball bearings, and it is the loudest component in my computer! My CPU fan is Speeze 8cm 2700 RPM rated (3100 RPM real world), PSU fan 1500-1700 RPM, HDD fans inaubible (I made a switch for them to 1. turn them off, 2. turn them on at low speed (inaudible) and 3. turn them on at high speed (loud). In winter, I set HDD fans to low speed (inaudible), and in summer at high (loud), but that loudness is not hearable beacuse of room fan cooling myself

So in winter, basically, only HDD is hearable in my computer.