Whenever I enter the Strip from Freeside, my game freezes and the autosave becomes corrupt.

Is there any way that I can fix this or get around it (that is, entering the Strip from a different location)?

Old old bug dude! Try searching!lol!

anyways check out this old link :
http://www.gamesas.com/index.php?/topic/1139743-the-what-i-did-to-avoid-this-bug-thread/page__p__16804076__hl__cowboy+hat+bug__fromsearch__1#entry16804076
A fullthread of bug workarounds.

Here's the one for your issue though.(whichi nicked off that thread.)

Bug: Going thru gate on north side reverts to black screen and no load-causing you to turn off console and reload.

WorkAround #1: Try this first..... Go to the guy at the trading post inside the Crimson Carivan fort and buy the Old Cowboy Hat. Wear it before walking thru the gate. (yes this sounds stupid....buuuut....so does a game that has sold so many copies from a reputable company being released with so many bugs) This used to never work for me other than getting me into the strip, only to have it freeze once I actioned a person or a door.....but that has since changed and seems to work every time. If this does not work, use workaround 2 below.

#2: Play from the CD ...not from the console. Avoid north gate like the plague. Use the Monorail EVERY time. Complete as many quests as you can that dont have to do with going in the 38 or Gammorrah until you absolutley HAVE to. At that time....make a BEELINE for the 38 or Gamorrah once you do load into that screen coming from the south entrance. Sometimes helps to give the game a minute to load and have NO Companions walking with you (have them wait somewhere like the Hotel Room at NoVac)....before walking one step from the gate. Dont talk to anyone or slow down at all. This works 2-3 out of 5-7 times. (yeah I know...still sux...but at least it works SOMETIMES)