Right now you are spending much more in power cost than you are getting by about 10-1.
You need at minimum an ATI 6970 card overclocked to about 400 megahash. That's what I got.
I get 1 coin every 3 days and it goes down consistently because of the increase in network power and difficulty increase.
I might end up with 50 BTC. It costs me $18/month in power and $400 for the card.
Paypal doesn't deal with BTC. You would need to trade it on an exchange.
You can look up current prices here:http://bitcoincharts.com/markets/
Last I looked it was around $14/BTC and I expect it could go down to $9 in the next week.
I plan to buy around $300 worth and if you want to accumulate some this is the route I would suggest for you as well until you get a 6970 or 6990.
CPU doesn't matter...at all. NVIDIA cards are also crap for mining as I found out with my 450 gts getting 39 megahash overclocked.
My UPS says my system burns 513 watts with CPU near zero and mining full blast.
You would at some point seriously need to consider wallet management and security.
I have multiple wallets with the main one never hitting the system and all are locked up in triple cascaded truecrypt volumes.
My mining wallet is the only one open to any hacking attempt and it always has zero in it until I transfer 1 BTC to the main one.
There are too many security un-savy people trying to do bitcoins and lots of them are getting their wallets stolen so be aware and make a solid security method to protect any investment you might make. Always consider that your computer already IS hacked.