Outlook - waiting to update inbox

Hello, I'd just like to start off by saying I'm a 14 year old kid who is in need of some help. Usually my Dad would deal with this sort of stuff but he recently past away so sorry if this sounds a little 'newbie'.

Okay, so when I start Outlook on a client machine I get the message 'Waiting to update inbox' and it says it's connected. After a very long time it got to 50% updating of inbox but this started happening yesturday and before it was almost instantly. I'm not sure what I can do to resolve this and I really need my emails back as I have some important ones coming through very soon. I've tried on a different client machine and the same thing happens. I tried going on outlook from the server but when I loaded it it wouldn't respond. I'm not sure what I can do to fix this.

Server running exchange server 2003
One of the client machines I tested ran Outlook 2007 and the other ran 2003. (if this helps)