A PS3 or Xbox360 for me and me alone? :-)

Hi everyone,
I know this debate has gone on since the dawn of time (time used loosely) but I'd just like to clarify some things about the two. Mods, please move this if warranted.

Basically, I've just finished college and for the first time have a bit of money on me. Have never been able to afford either console but always keep relatively up to date with new games and what not through my jealous, poor eyes. Finally, my hats going into the ring and I'm going to buy one but I have some questions that I'd like answered or clarified firstly.

Haven't had a console since the PS2 so know little or nothing about these two, never even played them to be honest (my mates aren't really into it) so forgive my amateur, pethetic questions.

Firstly, my game of choice would be single player games, live on my own and always preffered single player games with storylines. I'd obvioulsy like to go online a bit with the likes of COD and all that. Are their benefits or cons of either online systems? Is cost an issue (eg per year)? How do I even connect?!? Do I need a phone line or access to wi-fi? Which console if any is simpler and possibly more importantly, cheaper to hook up? I'm eircom, I imagine that won't be an issue.

Game cost for the moment shouldn't be an issue. I feel I have a lot to catch up on so wil be getting all the games I missed for pittance (GTA IV, Fallout, etc.)

Where's the best place to buy them? I was looking on play.com and from what I gather the prices seem pretty reasonable. If I buy, will there be extra costs associated with HDMI cables and stuff like that?

Also the hard drive size issue to me doesn't seem to be an issue at all. The only thing I'd want it for is for save points in games. I'd have absolutely no need to store movies/music on it. Will the smallest hard drive do me? Does online gaming require more space for any reason?

Basically I'd like to pay a lump sum for a console and pay little or nothing from there on in (obvioulsy not including buying new games). I know these questions have been probably answered to death so I apologise for that but just wanted to get your opinions on not which is better overall but what one would suit me.

I've posted this in the PS forum cause the only thing that I can differ them apart is the controller which as a PS2 player is the one I'm used to. That's it, that's all I know, pathetic I know .

Any advice would be greatly appreciated, thanks.