Hello,
when i had a 512k dsl connection, amule often taken all bandwith, hopefully, with the new 1024 dsl, it remains at 60-70 ko so i can browse and chat a little

aMule is fast, and u must have some misconfiguration problem.
New 1.2.5 aMule use much less cpu and mem: with ur config, u sould have less than 25% cpu and 10-15% mem
With Via C3 1Ghz 256 Mo i have:
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
fox 25834 21.5 7.1 29380 16144 pts/0 S 22:52 1:10 /opt/amule-cvs-db
Try to browse forum for config help and play with priority in both transfert and sharedfiles windows.
the polish
PS This is what u can expect when u have dl with a lot of sources (1024/128 dsl):