You're not thick, m8
Try...
Win 9x/ME: Start>Run> then type "winipcfg" (no quotes) & hit return
Win XP: Open a Command Prompt, & type "ipconfig" (no quotes) & hit return
-or- Double-click on your Network Connection (Start>Settings>Network Connections>your connection), select the "Support" tab, & click on "Details".
It should tell you your IP address, & when the DHCP lease is due to expire.