Hi there AstroMagic,
Both drives should do the job. You shouldn't really notice different boot/loading times between the two.
WD Black is considered to be a premium product, having 5 years of limited warranty. Also, it has a dual core processor, which makes it better for multitasking.
Even though it has slightly higher acoustics levels, WD Black should't be that noisy or hot.
More on their features:
WD Black:
http://products.wdc.com/support/kb.ashx?id=20RYS4
WD Blue:
http://products.wdc.com/support/kb.ashx?id=mKUf1Y
Let me know in case you have some more questions,
D_Know_WD