Vista accesing wireless network printer

I am a newbie, I guess I'm called. This is my first attempt to post a question for help and I'm not sure I'm in the right place. Anyhow, this thing has me going bonkers. I recently purchased a new Dell inspiron 1721 laptop computer AMD Turionx2 CPU, 2 GIG of RAM, 160GIG HD. It has been a nightmare,and Dell has been of little help. At this point, the computer is running not much better than my E-machines celeron lap top. It gets on my wireless network, sees the other computers, even sees the printer on my desktop (running XP media edition), but when I try to connect, access is denied. It is a shared printer shared by other computers on my network (running XP), and I am logged in on both computers as administrator, although Vista might not see it that way. The computers are all on the same workgroup, MShome. Dell wont help as they say as long as the computer goes on the network, thats all they will do. I think the problem is in a vista setting denying me access, but Dell doesn't help, and Microsoft refers me to Dell for help as Dell bought a group license and has apparently modified original code. I have a new computer with, I thought some tech support, but am denied by both Dell and Microsoft, unless I pay more $ for support. Does anyone out there have a fix for me, or have any suggestions on where help may be?
Captdavey