Without playing the first two titles, will I be able to jump into Disgaea 3 with no problems?

It just seems like a very daunting game, would it be easier if I tried to play the first two in the series first?

Yes.

Disgaea 1, 2 and 3 all have their own main story-lines (to the point where you actually don't miss much if you haven't played a prior game). Once you get into the post game you can unlock characters from previous NIS games, but knowing their story isn't important to doing so (note: I've only unlocked all story characters in Disgaea DS [D1 remake], and a few of the characters in D3, I haven't played D2 at all).

Also Disgaea 1 and 3 play fairly differently.

To my knowledge no NIS game shares main characters with another.