Using bitcoins is easy! You can send bitcoins as easily as sending email. All you need is the recipient's wallet address which looks something like this: 1PGFCtrJHUsc7fs4LGWLmXUEwuKyDaHuRa. Depending on the method you chose to store your bitcoins you simply enter the recipients address in the 'To' field, the amount to send, then send!
One thing which confuses people is the subject of transaction fees. Technically nobody has to pay fees to send bitcoins. However, this creates a problem because people can create spam transactions polluting the block chain by sending coins to themselves over and over. To discourage that miners, who are the ones that finalize transactions, prioritize transactions based on the amount and any fees. If a transaction is for a very, very tiny amount and includes no fee it probably won't get confirmed by the network for a long time, possibly days. Including a transaction fee even if it's very, very small helps the transaction to be confirmed on the network promptly. For larger amounts, say at least 1 BTC, including a fee is often unecessary. Any fees included go to the miner that finds the block which will include that transaction.
Another thing to understand is "confirmations". Due to the way bitcoin works it's generally said a transaction shouldn't be regarded as valid until it has 6 confirmations. This means that 6 valid blocks have been included in the block chain after the one that includes the transaction in question. The reason this criteria is used has to do with math and how hard it is to intentionally disrupt the block chain by beating the network with computing power. All you need to know is that it's very, very unlikely a transaction can be undone after receiving 6 confirmations from the network. Further confirmations make it even more unlikely the transaction can be undone.