I was asking length/filesize since I thought it would be easier to ask for that and work out the bitrate myself than just ask straight for bitrate
You can either use tools like
MediaInfo which I think is very good for giving technical information about media files, or in this case, since you told me the series and fansub group, I just looked up the file information straight on
anidb.info
Looks like 720p encoded with h264 in this case, but then your laptop's only an Intel Atom CPU, which isn't really that powerful either. Seems to be lower bitrate than their releases of the first series (same codec), so either maybe they're using more extreme CPU-intensive settings to get the filesize smaller, or they've gone more overboard with the karaoke effects

At least with the latter, you can temporarily turn subs off when things get heavy on the CPU (at least in Media Player Classic - I set "S" as a hotkey to toggle subs quickly)