anyone considering training for marathon/triathlon? or done it?

Hi all, I was just curious if anyone else has considered something well a bit drastic/organised training/big commitment like training for an endurance event.

I'm currently wavering, teamintraining.com has a great program, raises money for a great cause, and has great people supporting you all the way.

I guess my dilema is this. 1 it's a lot of money to commit to raise, 2 it's a lot of time/effort to commit to make (and my bf thinks i'll be tired all the time) it's every saturday morning all summer - oct, as well as tues/weds/thurs nights (this part wouldn't be a problem since i go to the gym weekdays anyways). but I will increase my endurance, strength, get the exercise in I'm wanting to, tone my body, all in a group organised setting (i really think this part would help me immensely), meet new people, and learn new routes around town.

I really think I want to do this, I was so pumped up after the last meeting I attended. here's the dilema though, I could choise to train to walk the marathon, run the marathon (here locally oct 1st), or train for triathlon this fall in monterey california. walking is the easiest choice, but somehow I don't feel I would gain a whole lot. I walk a ton on my own anyways, and walking a marathon, well doesnt' really seem like a huge deal. I'm pretty sure I've walked 26 miles in a day in the past already. and the other part, the walking team, by all means no offense intended here, but I'm 25, and in doing this would hope to perhaps make some friends out of it, and well it's a heck of a lot easier to find commonalities with people give or take your own age, and well the walking group is comprised of people mostly quite a bit older than me, not a real issue, but a consideration.

I'm not much of a runner, perhaps though this can be learned (but if i really don't care for running now can that be changed?), but ohmygosh would I love to have a runner's body...

triathlon, this is the biggest i think. bf thinks i'd need to train for a year to do this. no way 5 months would cut it. but i love to swim, yes loove, though I'd need to train for certain. biking is ok, running again defintely not my favorite, but the running part is only (ok yeah "only") 6 miles, that's not so far right? cons of this one: I dont' own a bike, lightweight bikes are rather expensive - but then I'd own a bike and could use it, and I do have one I can borrow from a friend for now. It would be intense. very intense. and the fundraising min for this is twice that of the local marathon, on the other hand i'd get to fly to california, stay with my teammates, celebrate afterwards (aparently dancing the night away helps ease out the soreness). and i think i'd feel an amazing sense of accomplishment if i completed this.

there is a midway (end july) recommitment date, where i'd have to decide for sure if i'm in, and can I 1st raise the funds and 2nd do this physically. So i could try this out, and see if it's for me. but i wonder if i dont' continue if i might feel worse than if i never start? but i really don't think i'd feel like i'd lost anything, just gained understanding of myself, strenght, endurance and hopefully lose a few pounds, and meet some cool people.

bf thinks the walking thing would be doable, still a lot of time, but ok. he's adamently against my crazy idea of training for a triathlon. it's all a bit crazy, but everyone i've talked to whose done this regards it as one of the best things they've ever done.

thoughts? i blabbed a bit about this in my blog to. the meeting is tomorrow night and i have to decide!
-Kim