It depends.. if your current modem is seriel port connected external then yeah it\'ll help slightly.. probly not enough to notice. Definately not enough to notice if you\'re using a USB external modem.
The biggest difference between the two is that the external one clutters up your desk while the internal modem makes everything nice and neat by including it in the package.. and IMO Internal components are always best unless you\'re absolutely starving for a free PCI or ISA slot. (Does your PC even HAVE ISA slots???)
Anyhow, I\'m not too hip to the new modem lingo either.. as far as I\'m concerened there\'s pretty much no difference between a V.90, V.90+, Flex, ect... it\'s all just gimicks to sell something "new" because they can\'t increase the speed of analog modems anymore due to restrictions set by the FCC. (AFAIK) You certainly won\'t notice a difference anyhow.