On the following blog, this person had a similar issue as you:
http://www.avforums.com/forums/windows-xp/948375-musicmatch-jukebox-v8-2-incompatibility-issues-internet-explorer-7-ie7.html
There may be an incompatibility issue, and you should try to contact Musicmatch to find out if there is a solution for this situation.
Another user in iguama.com reported this problem too:
I have a Dell xps with 1024 ram, windows XP pro and 120 GB. I installed musicmatch and it immediately disable my Nec 1100a DVD/CD read and write drive. I tried to enable the driver through my "Device Manager" (which showed the drive disable), and when I tried to I got error message that there was a program conflict and windows could not enable the drive. I sent a e-mail to tech support two days ago and still have not heard back.
The only other product I have that uses the drive is Roxio 7.
I have uninstalled musicmatch and used the windows "restore" to get my computer back to where it should be with my NEC 1100a DvD/CD--R/RW drive working just fine.
My advice is to stay away from this product because of conflicts that may arise with other programs and the p***-poor tech support !!!!!!
Here is a blog on the installation process, and seemed to work for one XP user:
http://forums.techguy.org/multimedia/504720-installing-musicmatch.html
Hopefully this will help.