You can keep searching for job, but if you can run one more startup that would be great. However startup is all about energy...if you are feeling you are not in any position to run one more startup...then completely focus on searching job and don’t take any job…as it will again make your resume weak.
There is no need to start small and re-build everything. I know there is a gap in your career...but you did something in that period, right? Show it in resume and show one skill which you can do properly. Don't show everything which you can do...if you are good in coding, show that, in sales…show that. But show only one thing.
Re-revise your resume.
Finally; if you still have enthusiasm and energy from inside...run one more startup, if not...come back again. But take a job first now, without any second thought. More doubts will drain more energy.
I would suggest you plan a new startup and execute it as early as possible...and at the same time look out for job. If you get a good job…that’s fine or else at least you are building something. But focus more on getting a job and show a proper skill in your resume.
If you are not good with the current technologies…see if you can be a business analyst or project co-coordinator position or something where you can show your functional side. Learning a new technology will be a waste of time now and will drain your energy more.
See what is the one best thing you can do and shape your resume accordingly…don’t make your resume as per your experience 4 years back and what is running in market.