Al,

How long is your tri- event this summer?

For a short one, I'd say just use platform pedals with whatever running shoes you'll be running in. The amount of benefit you can get from foot retention will depend to a great degree on how well you develop your pedaling stroke, and I rather doubt you can make significant progress in a couple months.

I use toe clips, I use two different clipless systems, and I use platforms. The way I pedal, it really doesn't make much difference.

Robbie is a forum member who, if I recall correctly, does triathlons. If he weighs in, I suspect you will find his advice useful (most of us have).