Hi G,
Thanks for writing in. As to your questions:
1) Given that your gap was several years ago, you should certainly explain it in the application, but I don't think it will impact you too much, certainly not as much as a career gap would.
2) I think top-15 is a good spot, top-4 may be a bit of a reach so you should maybe just choose one school from there, 2-3 in the top-10 range, 2-3 in the top-15 range.
3) If you think there's opportunity to improve your GMAT it could help you stand out more, but if your practice tests indicate you've about maxed out you're better off using that prep time on your essays.
4) See above re: how to approach which schools
5) Unfortunately MBA applications really only focus on post-college extracurricular work. You can briefly mention your college involvement on your resume and in the short answer part of the applications, but I would not focus an essay on this involvement.
Best of luck,
Daniel Richards
http://www.mbamission.com Read the
mbaMission Insider's Guides (14 individual school titles)
Visit the
mbaMission BlogFollow mbaMission on
Twitter