dial up help on windows 7
Dial up is slowest mode of internet.
Windows 7 has many inbuilt background connections(shadow tcip services running everytime)
Comodo free firewall. Close all unwanted connections to the internet.
Task manager >> services >>close unwanted services running in background
Anti virus program >>select manual update.
Set windows update to 'Check for update but install manually". (same for antivirus program)
Also full root level scan on computer to check for multiple malware detections. Avast, Malwarebytes, Spyware terminator free, Winpetrol (cookie checker)
Compress internet. Use k-meleon browser(good options to disable images, flash, animations etc), or opera with turbo(latest)
Fastun.com proxy (free but registration required) compresses non https connections. images,animations, etc.
Hope will help you..
Source: myself using a 3G limited connection very satisfactorily in India.