Problems with Wireless LAN Card Driver - Inspiron 1525 Vista

Hi,  I've had thisDell Inspiron 1525 Vista laptop for about 9 months and the wireless has worked fine until recently...  I've had to stop and restart the computer and modem lately due to problems.  My modem is at least 5 years old (Belkin)-  I have internet phone service (Packet8) and Wireless internet service (no DSL or cable where I live) Both have said that the connections look ok-  (download looked a bit slow, but not enough to cause these problems.)  My phone service is not working right and the computer goes in and out of connection.

Could this be my modem?  The last message I received is that my Wireless LAN Card Driver was causing the problem and I need updates-  but doesn't it automatically update my system?  Where do I go to update the LAN driver?  It is by Dell...

Thanks for any help,

Cathie