DL's on 56k can suck, but anything under 200mb's isn't so bad.
I've DLed 400+mb files in the past, all it takes is alittle time and effort; especially if you want it.
100-150 megs takes about 4-6hours at rates between 4.7kbs and 5.7kbs. If your 56k connection is slow or lags, get a connection utility like Befaster or NetMonitor to help keep you connection speed consistant.
You'll definitely need a download utility. Although Download Accelerator is the most efficent tool I've used for downloading, it's also the most problematic. If your not carefull the it will embed itself with internet explorer, forcing you to use it for every download. I personally prefer GetRight, just using the it's standard feature, none of the special 4-5 source downloading. It's quite reliable and wont screw around with Internet Explorer.
You should also find a good site to download from. Some sites give you a limited amount of -start- time to download a file (fileplanet's free service), so if you like me and like to pause downloads to play alittle HL, e-mail, or download something else, you'll need to find another site that will let you continue a download even if you paused it hours/days ago. The site filemirrors is helpful in the area of multiple links for a mod download.
Once you have your connection and download utilities, pick the site (the lets you resume downloads) your gonna download from and start the download. While it's downloading, clean up you bedroom, do some work, play another videogame (offline), or listen to some music. If you on one phone line and the connection gets cut due to a phone call (call waiting), you can always reconnect and resume the download. To disable call waiting put the *78 prefix at the beginning of the dial-up number.
With everthing set you'll have that 100+ meg file in no time.
Getting it through burning is a very good method because you get the file fast and have it archived on the CD, but it could become a hassle going to your friend for all your downloading needs. Plus, sometimes you'll get errors because of the CD quality and burn in speed. Hopefully if you use the CD burning method, you'll use the whole CD (all 600-750mbs) and use the slowest burn in speed.