Often times in the forums when someone has a display problem with their template and I can't replicate it from my Mac, I usually ask them for a link or a screenshot of the problem. I must say I am very surprised at the number of users who are still operating in Windows XP with ClearType disabled.
If your fonts look ragged or almost pixellated, you may be able to make your eyeballs a lot happier by turning on ClearType.
I highly suggest you run this tool for tweaking your display preferences. There are alot of other resources out there as well.
I came across a great example/article by a designer named Andy Rutledge about the purpose of HTML tags, and why HTML tags contain "no presentational value". His argument is to let the CSS handle all the presentation, while HTML tags only serve to provide "meaning and context to the content". Brilliant work, Andy!
Click here to check it out.