"Windows cannoit find http etc".

Hello,
Have lost the net/email. When try to go on line message is "Windows cannot find http" etc. Router is four place, two other machines on it working fine, The PC that will NOT go online is NOT put on line while others are running. PC was one of two in local network. XP HOME. I just did "Repaired" by XP. I did this in hopes what was wrong would be fixed. NOW at XP Sp1 status as cannot connect to SP updates. There WAS a virus before, something kept firing up MS Installing Scan which went off anytime you tried to run anything, more so to connect to net. Did some virus searches and killed a few that turned up, now that has gone away, but had to hunt down some that seemed to have come in with "repair".
TECH SIDE OF ISSUE IS.
Current status is PC is offline, cannot get to net or email. All offline programs work fine. NOTE PC gets VERY slow when I try shortcuts to net or t-bird for mail.. Mention this a very odd as REALLY bogs down then and only then.
Task manager window on network. Shows a .2% hit when trying to go online, about same for ping.
Attempt to go online, get messages
"Firefox can't find server at en-us-start3.moziilla.com"
T bird no mail states "Failed to connect to server at our mail site. en.us.www.mozilla etc etc"

Network adapter
Shows local area connection 10mbs connectivity
Has "address hard wired in as PC will NOT find address under automatic,
ISP confirms address nrs correct but is NO help on solutions.
Driver on card up to date, even switched ethernet card from working machine to prove HW was OK.
Ping results are
Address ping 192.168.2.100 Ping request now at 4 out, 4 back 128 ms
Preferred DNS Server 64 eetc time out. stats were sent =4 received =0
Pint computer (name) send 4 received 4 128 ms
Stats are for 192.168.2.100 and TTL=128
Nslookup is "timed out" etc "cannot find server name" for address
for both prime and secondary,
"Default severs are not available, Default server unknown"
Ipconfig is
Server Unknown 64.53 etc
Same if going for google (which offers ping)
ANY IDEAS here.
Something seems to NOT be connecting while ethernet card is connecting to router, Router works fine with other PCs. This thing went down with what seemed to be a MS INSTALL SCAN virus but NEVER found it.. got rid of some malware, got rid of MS install (AKA msiexec.exe) issue .
This seems to be some sort of XP failing as all else seems OK but not up to speed on how that works.
NO firewalls up ALL Antivirus removed.
Now stuck at SP home sp1 as cannot get on line for updates.
ANY data from bad PC must be put on CD and then run on this machine, as this one is online., NOTE to test PC I simply unplug the DSL line from bad machine and plug it in on this VERY old (1998) WIN98 machine and ALL works fine. has to be a SW issue. Not to good at the network. LAN etc, so need some help in this one. NOW seems something screwed up the net do it’s thing systems and not a clue where as HW seems fine and tests out OK! sooooooooo?????
Note am running Network adapter Icons and they seem to flash in and out on start up but NO www of any kind.
LESSON LEARNED
Does make the case for not tossing the old clunker out when you get a new one as this old 300htz cpu closet queen is working OK, a bit slow (VERY SLOW at CPU 300htz) but does works and can at least get it on line..