It will be fine. Heck I use the P120 365x Thinkpads for Mame and the classic games works great.
I mean you won't be able to play NBA Jam or the like, but if you have some of those old classics like robby roto, or the games made available from Star Roms, would work perfectly.
Are you going to use the LCD or a VGA monitor to view?
Let us know how you get on.