(1) It means the oscilloscope can sample the input signal at 10 million times per second, or at a frequency of 10MHz. CHeck to see if this is the sampling rate for periodic or aperiodic signals (at least I think that's what the terms where). THe periodic sample rate for a periodic signal will be much higher than for an aperiodic signal.
(2) This means that the oscilloscope will not be able to accurately measure signals that are faster than 2MHz (basically). It will not be able to measure frequency components of signals greater than 2MHz, and will not be able to do a fourier transform for frequency components greater than 2MHz.
(3) It can be used for both digital and analog, as long as the input voltage is not too high (different kinds of probes can step down the reading so that the oscilloscope can handle it). Oscilloscopes can measure voltage, frequency, period, and pretty much every other thing related to votlage like peak, minimum, etc. They cannot measure things like current, resistance, capacitance...
Why don't you just get a desktop oscilloscope? It's probably cheaper and more functional than a portable one. PLus you can't lose it. Do not think of an oscilloscope as a multimeter... or get a hobby one from Parallax or something that costs 1/4 as much, and then save to get a "real" oscilloscope. DO you actually need a portable one? Or do you just want one you can use like a DMM?
COrrect me if I'm wrong, it seems a bit strange to me that a scope can sample at 10MHz, but only has a bandwidth up to 2MHz rather than 5MHz. I can sort of see why, but it's not concrete. I've never given it much thought.