What pool are you using? It might be down. Slush's been going up and down the last 24hours.
Don't use GUIMiner to load CGMiner, use only 1 of the miners.
If you want to use CG just create a batch file add the following:
cgminer -o http://pool:port -u USERID -p PASSWD -I 10 -d 0
If you want to use GUI Miner its easy.Install/Unzip
Open GUIMiner
>Go to File (on top menu)
>>Go to "New Miner" ->click "New OpenCL miner..."
>Window will PopUp "New Miner<
Put a name you want for that Miner
Under Server:select your pool
Under Username:add your username. some pools like Slush's you need to add your Account User and Worker name. for example: JohnD.worker1
Password: will be the worker password
For CPU Affinity:Select 0, if you plan to mine Bitcoin as mining use GPU now.
If you need help, on creating a batch file let me know or more help ill do the best I can. Just provide me with more details on what you have pool, ect...
Also I recommend using BFG Miner instead of CG. -BFG Miner is like CG even the batch file is almost the same. just change cgminer to bfgminer.
BFG is ASIC compatible right out of the box.