How bad is it to tow an aircooled on a two wheel dolly? I may be pulling a vehicle about 6 hours back home..but all I have is a wheel dolly. Is this going to end up bad?

I've towed with trailers and tow dollies a few times, but I prefer to "flat tow" if possible.  It's pretty easy with a Beetle or Super Beetle . . . just requires the stuff RetBugtech mentioned (except that you will need 4 decent tires that hold air) and a special tow bar.

I once towed a 68 convertible from Orlando, FL to LaFayette, GA without any issues . . . well, besides the brakes going out on my truck . . . and loosing the drive shaft 3 times . . . and burning 2 cases of HD-40 oil . . . but no issues directly related to towing.  Later I towed the 68 convertible down west of Atlanta and towed back a 63 Beetle I traded it for.  I've also towed a Super Beetle from Murfreesboro, TN to LaFayette and made a few other 1-2 hour trips flat towing Beetles, Super Beetles and a couple of Karmann Ghias.  I couldn't start to count the number of short trips I've made flat towing old VWs.

Regardless of how you end up towing it, double check everything before you start moving . . . then stop and recheck everything after a mile or two . . . then stop and recheck everything at least once an hour or anytime you think something may be going wrong.  I think it was Mark Twain that said "It's better to be safe a hundred times than to be killed once."