Hi there, firstly i'd strongly reccommend you look at our Rogue guide on these forums. It should answer a lot of your questions. I wouldn't neccesarily agree with Ross when he says avoid the dungeons, certainly when I started in Northrend I went straight into the dungeons as thats where the best gear is found. With a few tweaks you should be doing enough dps at least not to be ridiculed.
Your weapons, they are both 2.60 speed, this is a huge no no. You need a slow speed a weapon in your main hand and a fast in your off. (Fast is 1.80 or below and slow is anything above that) so your number 1 priority is to find a fast off hand, even if it is a few levels below get it.
Apart from that your gear seems fine, enchant and gem if you like but its not essential untill you get to 80 and to be honest its a bit of a waste unless you have a lot of money because you'll be changing gear quite quickly.
Your spec is wrong, just with a quick look I can see you have points in things like Master of Deception and opportunity. Master of Deception is a stealth buff which will do nothing to improve your dps in 5 mans, and opportunity is for daggers and the general Mutilate spec, absoloutely useless if you're a combat rogue. Also you have points in Kick and sprint which is going to do nothing for your dps either. You also have no glyphs, you need glyphs.
I'd reccommend this spec as it's the cookie cutter combat spec. http://www.wowhead.com/?talent#fhg00...ocxqru0xRt:hkN
Copy all the combat talents first and then go on to fill out the assassination ones as you level to 80. Pick Sinister strike and Eviscerate first and then get Killing spree when you get your final glyph spot.
Third and final thing
Rotation! A rotation is the buttons you press in combat which absoloutely maxes your dps output. For combat it should go something like SS to three combo points, use Slice and Dice and then continue to use SS untill you have 4+ combo points and then eviscerate. Keep doing this and making sure you keep S&D up.
All this is pretty much in the rogue guide so do take a look at it. Amongst all this info is also all the info you'll need when you hit 80 and want to become a pro raider!