Limited connectivity via wireless and LAN

This is a Compaq Presario with Win XP Home 2002 with Service Pack2. It connected to my wireless router via a USB Netgear wireless receiver. In an attempt to upgrade to Service Pack3, I read on HP's site that an AMD based system must first install an HP utility prior to upgrading to SP3 else you'll get errors. In trying to install the utility, I received a message that my computer does not meet the minimum requirements. I've been in contact with HP's tech supp. Among other things, they had me install a .netframework update. It was about this time that I lost my wireless connection. I also uninstalled some other programs at this time, so I may have contributed to the problem.
The computer behaves as expected otherwise. It just won't connect to the internet either wirelessly, nor through an ethernet cable. In attempting to repair the connection I get a message that states the repair cannot be completed because my IP address cannot be renewed. I had a similar message while trying to repair the wireless connection. I had since disconnected the wireless USB receiver in hopes of being at least able to connect through the cable. With the wireless receiver connected, I could view about 8 available networks. One of them is unsecured, so I thought I'd try and connect to it, but got the same limited connectivity message.
I have since reset my Comcast cable modem, the D-Link router. I am online with my primary computer, the router connects wirelessly to my other computer and laptop, but this Compaq Presario won't connect wirelessly nor through the cable. I do have the setup disk for the Netgear USB receiver WG111T. Should I uninstall the .netframework update? I also have a ZyXell PCI wireless card as well as a Linksys USB wireless receiver with its install CD.
Is it worth trying them, or will it just be a wasted effort?

 

To follow up on the above, today I uninstalled .netFramework 2.0 service pack2, .netFramework 2.5 service pack 2, and .netframework 3.5 service pack 1. The limited connectivity problem persists.
I attempted to troubleshoot the connectivity problem through WinXp's internal help programs. Running a system scan shows the built-in network adapter Realtek RTL8139 PCI Family as passing. Of note, though is that the DHCPServer=255.255.255.255 is flagged as an "invalid IP address ". The IP address of 169.254.62.253 shows as "Passed" .
I next tested the TCP/IP configuration using the command prompt, typing in "IPCONFIG" I get the same autoconfig IP address, but the subnet mask shows as 255.255.0.0 There are also a Default Gateway and a Connection Specific DNS suffix, but they are both blank. Pinging the loopback address shows no loss of packets with 0 ms round trip times. Then I pinged the IP adddress of the computer and it returned the same results as above-no loss and average 0ms transit time.The next two steps are to ping the remote host and the DNS server. I don't know either of those addresses. I did attempt to ping 255.255.0.0 and got an invalid destination as a return.
How do I find the IP address of my router? What is the consequence of my having deleted those 3 .netFramework items?
Thanks.

 

Well, I threw in the towel and just used the recovery partition to restore the computer. All is well. Some work left to do, but overall, I believe this is the path of least resistance.