oh whoopy skip, thought they might have worked out bugs since fo3 was riddled with them, well after playing again this morning I noticed the glitchy jumping is down to non existent must only occur after hours of gaming
You may notice after your file size is in excess of 10 mb you will have more frequent crashes/glitches. a little bit of lagging is normal, it's just trying to load terrains and scripts etc. when you walk into different areas . there isn't really a way to avoid this, as you can't play the game if it isn't loading things.