dude it's really it's up to ...
get songs that intrest you more than anything , no matter what , and take your time , you see it's not about what you play , but how you play it , well at least i think , sometimes the best thing to do is to start slow and progress from there , any tune , riff you find a little hard to play just slow it down and do it Really slow , and build your speed from there on ...
learn to play muted notes , semi muted notes , full unmuted , and to be able to hit the strings right with and without the pic ,
and actually get comfertable with the guitar and the way you hold it , you will be surprised to know how many people can't play classical guitar "just to play it , not to do classical" and how many good musos that still strugle with there pics lol ,
get someone to show you a little bit here and there , and learn to use the whole neck when you can , and if something is getting frustrating , don't just leave it and move on , keep at it till you get it , i know many people who can only play half songs because of that lol .....
train your ear to pick up all the guitars in a song , and fucs at one part at a time ... if you gonna do metallica , then maybe it's good to know how to play what james does instead of jumping into what kirk does half way through lol .......
being a good Rythem player is HARDER than learning solos when you are starting out ., trust me ..... mahy people can fidle around with scales and solos , but there rythem tech is really bad ,
and like the rest said , metallica , specially that Black album , it's really easy stuff , but still good way to get your playing on track , and maybe a bit of Megadeath too ...
but like i said , don't stress it out , take your time , it will take you years to get good , so don't rush lol , and practice , practice and more practice , great words that Rhods "RIP" said once , and they are like the gold of the industry ...... you can never have enough ....
Remember if you are stuck , ask , and keep at it , and Good luck
for one day we might jame