Is it doing this with all websites or just this one?
Just checked that site out, and it appears to be as it should.
Also, have you tried using another browser?
Initial thoughts are that the default css styles in IE have mysteriously changed and are overriding the sites css styles.
Have a quick look through these options and make sure nothing is set.
My Computer
At a glance
Windows 7 EnterpriseIntel Pentium Dual E2200 @2.2GHz4GBPalit GForce 9500GT 1GB