IM going to assum you have no firewall running on the pc that is blocking anything, if u have ANY firewall running I suggest uninstalling it testing then if u get connected then sorting out the firewall, however proceed below on the grounds there is no firewall running.
Ok quick check list
(1) window > START > RUN > CMD > OK > IPCONFIG
IP = 192.168.x.y
Is this the IP you have forwareded the ports to?
(2) mirc > tools > options > connect > options > advanced
Start = X
Finish = Y
Are these the ports you forwarded in the router?
(3) Router > Security > Disable Firewall Protection >
Setting = Disable
Has this been done.
(4) Router > Security > Block Wan Requests >
Setting Disable
Has this been done. (i know it didnt say to do it but it does say to do it on other linksys models, although i never found the need before)
(5) Router > Status > Internet Connection >
IP Address = a.b.c.d
Is this your actual internet IP address or a lan ip such as 192.168.x.y or 10.0.x.y?
(6) Router > Applications & Gaming > Port Range Forwarding
There are no conflicting forwards to other Ip's?
(7) Router > Applications & Gaming > Port triggering
This is empty?
(8) Router > Applications & Gaming > DMZ
This is not on?
(9) Router > Applications & Gaming > DMZ
set on, and set IP to your PC's IP **** warning a firewall well be needed in the long term if this option is left in play ****
If none of these work email me ill tell you were to conenct to me or someoene else who can likely sort ya problem out, but do please check these first, as the same thing is likely to be asked of you by me or who ever might help you.