iLemming with an Intel Question

Please don't laugh (too much).  I need to help upgrade my aunts computer and she won't have a Mac.  Doesn't want to learn a new anything.  Her present machine is 133MHZ, 16MB RAM (72 pin SIMM) no USB, running Win95.  She can't spend more than $200.00(US).  I haven't used an X86 since Windows 3.1 but I'm the IT.

Question:

What do we want to be looking for?
Thank you

Too much FUD in this thread. Windows XP is much better than Windows 2000 in a lot of ways now, especially in networking compatiblity, ease of use, and some other crap I forget.