ok i know that this question is kinda stupid but, if i take the talent that lets me take a combat feat, i still gotta meet the prereqs right? i mean, i cant take for example, weapon specialization because im not a fighter lvl 4 right?
Correct. Combat Trick, for example, gains the rogue 1 combat feat. If you look under Combat Feats it says you have to meet the prereqs. So you could not take Weapon Specialization unless you met the prereqs for it.
The other two talents that spring to mind grant the rogue either Weapon Finesse (no prereqs needed) or Weapon Focus (BAB +1 req'd). By the time you get your first talent, you will have BAB +1, so you're fine there.
There may be some talents in newer books that bypass these restrictions, but if so I'm not familiar with them.
If a talent gives you a specific feat and you qualify to take the talent (usually only req is Rogue 10 if it's advanced, or knowing some other talent first), you get that feat even if you do not meet the feat's requirements. If it's something like combat trick that lets you pick one, you have to qualify for the one you choose.
thx, i hate when this questions come to my mind at work (i cant check the SRD cuz the computer here say some crap about proxy filter blah blah)