To answer your questions :
1-Many people still mining LTC and yes it is still profitable ( google litecoin calculator) .As far as hash rate , that depend on your mining gear. Please see the litecoin hardware comparison list here :
https://litecoin.info/Mining_hardware_comparison
2-I do strongly recommend auto profit switching pools like middlecoin :
http://middlecoin2.s3-website-us-west-2.amazonaws.com
It will automatically mine the most profitable coin and pay you in btc. If you just want litecoin pools see this page for a list of all pools:
https://litecoin.info/Mining_pool_comparison

Most people use cgminer. Here is a list of mining softwares :
https://litecoin.info/Category:Mining

1. I am approx. 110-120MHs

2.  I mine at several different pools to distribute the hash rate.  
My favorites (in order) = coinotron.com, p2pool.org, litecoinpool.org, litebonk.com

Is it a mistake.  Depends.  Are you trying to get rich quick?  Is so yes, it will suck as much as it will be fun.  Are you in for the long haul and plan to add on?  If you can handle the frustration, electrical cost, the endless tweeking, and times when you can't turn a profit then it will get better.

What did you buy for $2000?

I am hoping he got lucky and scored 5x 290s. My feeling tells me that was not the case