Hi my names jon I've been going out with my girlfriend for 5 weeks, the problem is that we don't connect with each other which is weird because I can talk to lots of people including girls and I can have decent conversations with them so far I have managed to get a couple of one sided conversations going but that's about it. We sometimes talk on msn.
She sais that she likes me when I ask her (as I do to) but I can't seem have a decent conversation with her
Its not just conversations, we have hugged on 5 occasions (one for each week) and I kissed her on the cheek once
I don't won't to dump her because she is really nice but I can't seem to talk to her, she isn't shy around her friends just me

So my question is this is it me or her and what should I do

It's been 5 weeks, so it's still somewhat new. Some people take more time to get comfortable with others. The thing about people are, you can have to great decent people, you put them together and thy may not click. Everyone has different definitions of a decent conversation, and it sounds lke the conversations you have had are not up to your expectations.
Are you yourself around her? She may hit it off with her friends more than you because she's known them longer and have more points to talk about. My ex said the same thing about me, that I hit it off better with my friends. It's normal to have different conversations with your friends.

Can you not talk to her because you have your guard up or trying to hard to make an impression? You have to be yourself because in the end, if you are not yourself, you will regret it.

As stated earlier, 5 weeks is still short. Give it some time to connect. Maybe you can bring it up casually and see if she feels the same way. You sound like a guy who cares, so if you feel this might not work out, ask yourself what would you regret more
1. Not giving it a chance to see where it goes. Or
2. Giving it a chance and possibly not working out.

Good luck.