Play lots of freerolls to build a bankroll and then you can play a few micro stakes SnG's and MTTs to get a feeling of what is best for you. I don't think there is a definitive anwer to your question. You can grind and make some money with SnG, but the big cashes are all in MTTs. I like to play both, but only you can decide what fits you best.
Like Roc said, it depends on what you like and what you can do. SnGs are usually shorter but pay less. MTTs are way longer and pay way more. Start out with single table tournaments to get a feel for what you like and if you find success in it then try bigger tournaments. Some people are naturally hardwired to one or the other, in my opinion. Many excel at both but it's more important to stick to one and master it so you can increase your profit. If you play every game type you'll never get to know one inside out.
MTT - players can be tens of thousands, and the game can last 12 hours. and when you get to the final table is unknown. it's also obvious that big capital is needed for mtt, because you can retire 100 times before you reach a win, before you win, because there are approximately 10,000 players.
sng - there are few participants, and you need less capital, and you can get prizes in the very first game, but it happens that the rake is high, and at your limit there are a lot of good players, and a few fish
for beginners freerolls (if you do not want to deposit) and you can start your bank from 0, also with the free ones you can start to get a little more experience and apply the knowledge you have, then when you have enough bank you can play sng to go experiencing more what it is to play paying a ticket, and when you have more confidence you can play both, sng and mtt, the sng are also very good and are important to make your bank grow because in them you can invest less time than in a mtt , of course the profit may not be the same, but try to look for the positive and negative side to each one
Which tournaments are best for the beginner to play. SnG or MTT?
Make sure you practice bankroll management through your learning. If you learn right the first time then you won't suffer the fate of 99% of potentially great poker players who never made it due to bad bankroll management. As such, they were never able to climb the ranks. I believe I strongly fall in this category but I have greatly improved as soon as I took ownership.
Sng's are best for a beginner. If you play on stars, play the 1 dollar 180man and the 45 1 dollar 45 man tournaments. Play regular and slow speeds.
Avoid turbos. Slow games give you a lot of room to maneuver and room to recover when you **** up or take a big hit. And most importantly the slow games are played by people who are serious and want to either learn or make money.
The turbos are played by lot of of action junkies and some regs.
I would recommend that you play a minimum of 1000 of these games. Before you move on to the 45 man turbos.
What's more is that the slow tournaments will not hurt your bank account too much. Depending on your level of skill, you might even make some good money playing them but if not it's cool. Unless you are completely new, you should at least be breaking even while you learn.
When you start final tabling 10%+ of your games then you can graduate to the 1.50 45 man turbos.
The 45 man turbos are a great way to learn how to navigate late stage play in tournaments.
They are actually really great for learning all stages of a tournament but more so late stages.
These ones have the potential to hurt your account if you are reckless.
I'd recommend that you play at least 500 of these games before you move onto Mtts or Bigger SNGs.
During your learn phase, don't move on until you are making profits on each phase. It will be a pain in the ass but the reason you shouldn't move before you start beating the games is simple.
If you are not beating the games the your skill level is still improving, which means you don't have what it takes to be those games yet. Why would you move on to a tougher game if you can't beat your curse t stage?
That will only widen your skill gap even more so and you will hate poker for it.
On my experience, my gains were most out of SnG. It is faster and usually with less players. My favourite is fifty fifty from pokerstars, the turbo version takes usually 30min to finish and if you finish in the top 5 you get almost the money you paid to enter plus the chips value.