Are there many simple yet versatile openings that provide an opportunity to reach a balanced middle game without having to learn a ton of theory?  I am looking at the Torre Attack presently and would like to learn an e4 opening with these qualities as well.  Any suggestions? 

The stonewall attack for white is perfect.  Hardly ever any new red hot theory to learn. 

Thanks knightassassin.  I have read that the modern defence is solid against d4 and e4 openings.  Can anyone confirm this from their own experience? 

reti opening is good or even the spanish game

Yes, I can confirm from my own experience that the Modern Defence 1...g6 2...Bg7 is good against 1 d4 and 1 e4.

Certain defenses (The Pirc, The King's Indian, or Modern) allow White to build a classical center within the first few moves, and so can be classified as "systems" against either 1.e4 or 1.d4. (If course, playing 1...Nf6 in response to 1.e4 will usually not transpose into a King's Indian.)

Some flexible Openings for White include: The English (1.c4), the Reti (1.Nf3), and 1.b3 (Not sure what this is called!) Flexible Openings for Black: The Modern (1...g6), 1...e6 (Can transpose into tons of different defenses.), and 1...d6 (Again, can transpose into many defenses easily.)

Basically all those non-mainline d4 systems are easy to learn and playable.

As black, the Scandinavian and the Queen's Gambit Declined are both simple enough to learn and totally respectable.

Try the Stonewall Attack for white. For black, I suggest the French against e4, and for everything else, the Dutch Stonewall, starting with ...d5, instead of ...f5 as to avoid all the anti- Dutch gambits.