Okay, mic pre amps....
The electrical output of a microphone is very, very low. Compared to the "line level" output of things like a keyboard or a CD player, microphones are something like 40 to 60 dB quieter. Therefore, to bring them up to a level that things like mixers and interfaces can handle, the first thing the microphone goes through is a "mic pre amp". The brings the "mic level" signal up to "line level" and, importantly, does it without adding more noise or distortion to the signal--i.e. despite how common they are, they're quite an impressive bit of kit.
On interfaces (such as the Tascam that was being discussed) the mic pre amps are built into the interface. Usually (but not always) if you see an XLR input for a microphone, it implies that it will go through a mic pre amp.
Most interfaces have a mix of mic level (i.e. with pre amp) and line level inputs (i.e. no pre amp). This is because it's pretty common to want to record things like keyboards and electric guitars (instrument level which is different again--but I won't go into that now!). This is normal and all you need to make sure is that you have an appropriate number of each type of input.
So...basically that was a long winded way of saying "don't worry about it".
As for the mics, I've owned a couple of Studio Projects mics (a B3 and a C1). I really liked them at the time--they were among the first inexpensive large diaphragm condensers to offer very acceptable quality. However, in recent years I think they've been a bit over taken by some newer models. I'm now a big fan of many of the offerings from sE electronics--the 2200A is a marvellous mic that I frequently use in preference to things like a Neumann TLM104 which is 3 or 4 times the price. That's my own personal take (based on the things I record) but those might be worth a listen.
To my ear, I prefer the C1 to the AT2020 (but don't know the 2035). I prefer both those to the MXL990 which always sound a bit woolly and lacking in detail to me--I've sometimes used an MXL 990 on drum overheads or screechy violins to get rid of the HF detail-- (and, again, I've never used an MXL770 in anger). But, depending on your local prices, suggest a listen to some sE mics.
Hope this helps.