re: Poker & MTT difficulties
For a quick start, read the strategy articles on this site if you haven't done that already.
The best book on tounaments is Harrington's 3-volume set. First 2 volumes go into a lot of detail how to play tournaments. The 3rd volume is a quiz.
Another good book is Skalnsky's book on tournaments.
Here are a few pointers on how to play MTTs.
When blinds are small, play tight. Basically AQ or better(perhaps AT,AJ from late position). Limp or call a small raise with any pair from any position and if you don't hit a set, fold on the flop. From middle and late position, you can play SC 45 or higher. Don't overbet as it increases pots too much and foces you to risk large percentage of your chips(or all of them).
When blinds get bigger play a little more aggressive and add more high cards, like QK. SCs are now not as good as your stack is usually smaller. Same applies to small pairs. Also, if you haven't been moved to another table in a while, use your tight image to steal some blinds or bluff at a pot in position.
The above should get you to the late stages of the tourney quite often. In that stage, you will often have a small stack(even if it is an average stack). SCs are almost worthless since you don't have the implied odds
to draw. Small pairs are also trouble. Play mostly big cards. Steal more blinds when you get a chance. Best situation for blind stealing is you are first in the pot, the blinds are small or medium stacks and tight. When you have less than 10BB, you should go all-in pre-flop with any pair or very high cards. However, if there are limpers or raisers in front of you, very small pairs may not be good, and you are more likely to get called.
For final table play, play some SNGs to get some sense. The SNGs, however, start with big stacks and you will rarely have such stack at the final table.
Finally, read posts on this forum and twoplustwo.com There is a lot of very good and detailed information.