XHTML strict elements and attributes

I'm making the switch from HTML to XHTML strict. I used a validator and received a lot of results that don't make my document(s) valid. All of them had to do with attributes and elements. I was wondering if there were any websites that tell you what you can do to replace them.

Examples: <br />, <center>, width, height, target, input, align, etc.

I don'tnow of a website off the top of my head but here is my two cents:



1. br looks fine; this is a wellformed empty tag
2. center tag is deprecated so i am not sure if that gives you a problem but remember all tags must have a closing elemnent or be properly formed empty tags(ie. <center /> or <center>Foo</center>)
3. width, height, target, input, align, etc: all attribute values must be double quoted.
valid: width="100" target="_blank"
not valid: width=100 target='_blank'

I hope that help you get started...

Line 23, column 26: there is no attribute "align"
<table width="98%" align="center" style="border-collapse: collapse">
^

Line 232, column 10: there is no attribute "width"
<td width="98%" valign="top">
^

Line 232, column 28: document type does not allow element "td" here
<td width="98%" valign="top">
^

Line 268, column 25: document type does not allow element "td" here
<td id="td4" valign="top">
^


I've been working on converting my website to XHTML strict (It was a lot of work to do, but it was time well spent ) These are the last four things that are left to fix.

1. I found out that Mozilla the following CSS style:

table {
margin-left: auto;
margin-right: auto;
}

But this doesn't work with Internet Explorer.


2. I made the tds that needed to, have an id then I set the width and/or height for the td using CSS. I tried doing this for this one but it looked horrible.


3. I have one big table and have everything inside this table. I don't understand why this won't work. It is for a big portion of the page.

4. Same as number three.


So since I have come to a point where I don't know what else to do, I thought I could ask you.

As far as i know, _target is not allowed in (x)html strict, and the alternative could be :
onclick="window.open('newpage.html'); return false"
in place of target="_blank"
It's javascript, so if the client doesn't support that, it will open the link in the same window

p.s.
i'm in my first post here, i'm just looking around. Plkease forgive my inexperience

Marcello