the download is only for the original wow. u have to buy tbc if u want to play the expansion. after trial period u can either buy a cdkey from blizzard and upgrade online or buy a copy of the game and upgrade your account online too.

servers are not connected. what you have on this server is for this server only.

wat do u mean by dota lagness? like if u lag, other ppl will get a waiting for <player> msg? then no, if u lag, it's u alone only. other ppl will not be affected by your lag.

UI stands for user interface, they way the buttons are placed in your screen. u can get custom UI at www.curse-gaming.com dunno if they are still there or not coz i left the game 6 months ago but recently decided to play again.

zboard isnt worth it imo unless you are hardcore and with lots of cash to burn

better try oceanic server. go for any new server as you can get lots of new players starting out and can get lots of new ppl leveling together.

you have to choose either to go for pve, pvp or rp-pvp server.

pve = mostly for pve oriented players with occasional pvp

pvp = for players who like pvp and pve together

rp-pvp = the so called "polite" pvp server. no trash talking and doing stuffs that might disrupt other ppl's gaming experience.