When I started Wizard 101 I first picked a Death Wizard but it seams that the death wizards have to use more strategy then other wizards. I'm not saying the other Wizards don't but if you want a strong attack you need a lot of shields. This may not seem like a problem to you but it was for me in Krock and sometimes in moo. Sometimes I have to heal but if I do that I take away a shield but if I attack there is a big possibility I might be defeated. If you are a new death wizard good luck you'll need it
Not really, I am a hard core solo wizard, The general school is a solo school you just need to do it right and your fine. I would have to say that death is the easiest next to fire and storm.
The easiest school is really whatever school you like to play. I have soloed every world with all schools except Fire (I don't like relying on DoT). I found Myth is the easiest overall at all levels. Death and Life are both easy to solo but take some hard work at middle levels before they get attack all spells. Ice gets harder to solo bosses around Azteca and tends to take longer setup. Storm is easy but sometimes it's all about the luck of getting the spells and pips at the right time. It involves a lot of dying and quick battles. Balance takes a lot of thought and work to solo but can be very fun. Every school can solo most of the game, there's only a handful of dungeons that require a team.
For me death is probably the easiest to play solo with because of all the drain spells. No need to waste time and/or pips drawing out the battle with shields and heals, just buff and hit with a drain spell and march out of the battle with full health.