LCDs typically work at 60Hz when using a DVI-D connection. An analog connection using just a normal VGA cable will allow a refresh rate of up to 75Hz.
What's the benefit of higher refresh rate? nyet, nil, nada, nothing... etc.
LCDs and CRTs do not operate the same way. LCD relies on response times and times like 2ms is simply marketing. That represents the best possible ideal situation. Plus there is no standard used by manufactures to actually test how fast a monitor is.
Most people will tell you analog and digital connection doesn't make a difference anymore. That's more or less true, but there are some monitors that simply looks better with a digital connection.
Don't get too caught up with refresh rates and response times.