Get the hell out of iPoker ASAP its absolutely horrible place for learning poker. You can cash out anything above $50 I believe so don't hesitate to do that (and you will have the $50 on ipoker for fun SnG's or just a reserve if you go busto)
NL10= Almost only shortstackers.
And when you got a bigstack then he is a nit usually.
NL2= Incredible nitty PF, VP15 Minus on average. Its VERY frustrating to play
NL4 =Only playable limit with 3-4 normal stack people at the table usually. Still very nitty.
Micro stakes on iPoker are only about playing with ridiculous nits and many many multitablers and waiting for the 1-2 fishes that come and are immediately stripped of their money by the nits.
Usually what the saying is LAG > TAG, with taking many blind steals etc. but you won't be able to play LAG at this level.
Also, i wouldn't ever go to Stars for SSS NL10, although the tables are loose Stars hate shortstackers so I'd go for PartyPoker.
However, if you are not a sissy than I'd move to big stack NL2, first buy in for $2 and gradually increase it dollar by dollar ( I Strongly reccomend BR around 30Byu-ins when you will have them at this stage as tilts will come if you open up your range according to the Pokerstrategy chart).
And Stars are perfect for this, as there is no problem finding 6 tables with 50%+ players per flop!
And if you can't cash out anything than I am afraid the SnG's are really the best idea if you can play them profitably and iPoker is actually really great for those (Unless you are so good to play short handed, 6MAX tables are ok on iPoker) . I wouldn't get into limit if you prefer to be a NL player as you will get some bad habits from it.