This is a bug report. DOSbox 0.61 seems to be locking up occasionally when trying to perform disk I/O. It's happened to me a couple of times now, once with Mad TV 1 and once with Centurion. It locks up completely when I click on save, and interestingly in both cases, just when the cursor appeared for me to type a name for the save game. Can't say it's easy to reproduce though. Yes I've read the readme.

System specs:
Athlon 1.4ghz
256mb ram
nVidia Ti200 graphics card
Via AC'97 onboard sound chip
Windows XP