Early 20's i use yahoo mail for that time but the problem is so many advertise and so slow either then i decide to change from yahoo mail to google mail.Google mail is the best among those mention so fast,easy and manageable.
Gmail without a doubt. The features, the look, the LACK OF SPAM. it's great. Hotmail has actually gotten better with the latest upgrade but the only drawback is it seems very unorganized and crowded now. Yahoo Mail looks better and more ordered than Hotmail layout wise. But the spam is just too much. That's why I left it years ago.
As for me, I am more into Google mail. Since I am an android user, the phone has its own built in google mail application. Thus, the google mail can easily make notifications with my phone and I get easily updated with the latest trends and emails. But I guess there's no such large differences with hotmail, google mail, and yahoo mail as long as you use these sites for just making email.
I'm currently using GMAIL and I recommend this for you. Before YAHOO is the commonly used emails but since it has over a million registrant it came prone to hacking and virus. When it comes to the display GMAIL is more modern and updated, unlike YAHOO until now its not update although the security of yahoo is great.
I haven't used hotmail for quite a while. Honestly, I forgot it still exists. I mainly use yahoo and gmail. On my pc it's gmail that I normally use because I also use it for my other sites like youtube. Gmail fairly loads faster than yahoo. But on my mobile I'm using the yahoo mail app, The app lets you add account even if its from a different mail provider and very useful in checking multiple emails. Quite fast too.
I have both yahoo and gmail account, my yahoo account I'm using it since I was in College and until now.
As far as I observed you can create you gmail account in an easy way and it is easy to use. Not like others email, the theme is very simple yet elegant.