Go for it! It's fun and it's a reasonable goal. Don't mention to DH that you are planning on doing it until closer to the time, if you don't expect him to be supportive. Mine is just now getting into the spirit of my running. Now, he's saying "isn't today your running day? Go run, I'll fix dinner."
I joined a running club that has some beginning runner programs. I did my first 5 K last month. It took me 44.16 minutes to drag myself to the finish line and let me tell you I was sure they had mislabeled the course, it had to have been longer then 3 miles...
There are lots of heavy people running the 5K's. Just make sure you train properly. Do you have a training plan?
This web site has great information for new runners.
Check and see if your local running club has beginner programs. For me, it's been great for the accountabiltity. I run 2 x a week with the group and 2x a week by myself. I have to do the times by myself because I won't be able to keep up with my friends when we run as a group.
Also, some of the running shoe stores will sponser programs.
is one example.
How fast are you running? Check and see how long the course will be open. Some 5K's are for speed and they close the course after a set time. Most are fun runs and they leave the course open until the last person strolls in.
Good luck, train smart and have fun.
49 years old, 5' highest weight-199lbs
. Started SBD Jan 2004, lost 47 pounds in 6 months, then slowly gained it all back.