I can't see why you couldn't use this drive in a desktop machine without making any changes other than the obvious physical ones. The only thing that comes to mind is ERC (Error Recovery Control) which imposes timeout limits on read and write retries. ERC is typically used to ensure that a drive doesn't drop out of a RAID if it remains busy for too long. Desktop drives don't usually enable ERC.
Your other question regarding laptop use would depend on whether your laptop's SATA power connector provides +12V. The ST9500530NS requires both +12V and +5V, whereas most laptop drives need only +5V. AIUI, most (all?) laptops don't provide a +12V supply for the HDD. In fact I recall a thread at Tom's Hardware where a laptop user was unable to get his enterprise drive to work for this reason.
Product Manual - Constellation Serial ATA - ST9500530NS / ST9160511NS:
http://www.seagate.com/staticfiles/supp ... 38694d.pdf